{"id":4963,"date":"2023-03-16T07:22:22","date_gmt":"2023-03-16T07:22:22","guid":{"rendered":"https:\/\/theexampillar.com\/ncert\/?p=4963"},"modified":"2023-03-28T06:14:47","modified_gmt":"2023-03-28T06:14:47","slug":"ncert-solutions-class-9-science-chapter-4-structure-of-the-atom","status":"publish","type":"post","link":"https:\/\/theexampillar.com\/ncert\/ncert-solutions-class-9-science-chapter-4-structure-of-the-atom\/","title":{"rendered":"NCERT Solutions Class 9 Science Chapter 4 Structure of the Atom"},"content":{"rendered":"<h2 style=\"text-align: center;\"><span style=\"color: #000000; font-family: georgia, palatino, serif;\">NCERT Solutions Class 9 Science\u00a0<\/span><\/h2>\n<p style=\"text-align: justify;\"><span style=\"color: #000000; font-family: georgia, palatino, serif;\">The NCERT Solutions in English Language for Class 9 Science <strong>Chapter &#8211; 4 (Structure of the Atom) <\/strong>has been provided here to help the students in solving the questions from this exercise.<\/span><\/p>\n<h2 style=\"text-align: center;\"><span style=\"color: #000000; font-family: georgia, palatino, serif;\">Chapter &#8211; 4 (Structure of the Atom)<\/span><\/h2>\n<p style=\"text-align: justify;\"><span style=\"color: #ff0000;\"><strong>Questions <\/strong><\/span><\/p>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>1. What are the canal rays?<br \/>\n<\/strong><strong>Answer &#8211;\u00a0<\/strong>Canal rays are positively charged radiations that can pass through perforated cathode plate. These rays consist of positively charged particles known as protons.<\/span><\/p>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>2. If an atom contains one electron and one proton, will it carry any charge or not?<br \/>\n<\/strong><strong>Answer &#8211; <\/strong>One proton has one unit positive. Similarly, one electron has one unit negative charge. An atom with one proton and one electron will be electrically neutral. The charges will be balanced inside an atom.<\/span><\/p>\n<p style=\"text-align: justify;\"><span style=\"color: #ff0000;\"><strong>Questions<\/strong><\/span><\/p>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>1. On the basis of Thompson\u2019s model of an atom, explain how the atom is neutral as a whole.<br \/>\n<\/strong><strong>Answer &#8211; <\/strong>On the basis of Thomson\u2019s model of an atom, an atom consists of a positively charged sphere. The electrons are embedded in the sphere. The negative and the positive charges are equal in magnitude. Hence, the atom is electrically neutral.<\/span><\/p>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>2. On the basis of Rutherford\u2019s model of an atom, which subatomic particle is present in the nucleus of an atom?<br \/>\n<\/strong><strong>Answer &#8211;\u00a0<\/strong>As per Rutherford\u2019s model of an atom, the positively charged protons are the ones that are present in the atom.<\/span><\/p>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>3. Draw a sketch of Bohr\u2019s model of an atom with three shells.<\/strong><br \/>\n<strong>Answer &#8211;\u00a0 <\/strong>A sketch of Bohr&#8217;s model of an atom with three electron shells is shown below:<br \/>\n<img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-4996\" src=\"https:\/\/theexampillar.com\/ncert\/wp-content\/uploads\/2023\/02\/NCERT-Solutions-Class-9-Science-Ch-4-Q-03.png\" alt=\"NCERT Class 9 Solutions Maths\" width=\"544\" height=\"318\" srcset=\"https:\/\/theexampillar.com\/ncert\/wp-content\/uploads\/2023\/02\/NCERT-Solutions-Class-9-Science-Ch-4-Q-03.png 544w, https:\/\/theexampillar.com\/ncert\/wp-content\/uploads\/2023\/02\/NCERT-Solutions-Class-9-Science-Ch-4-Q-03-300x175.png 300w, https:\/\/theexampillar.com\/ncert\/wp-content\/uploads\/2023\/02\/NCERT-Solutions-Class-9-Science-Ch-4-Q-03-480x281.png 480w\" sizes=\"auto, (max-width: 544px) 100vw, 544px\" \/><\/span><\/p>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>4. What do you think would be the observation if the \u221d\u2013 particle scattering experiment is carried out using a foil of a metal other than gold?<br \/>\n<\/strong><strong>Answer &#8211; <\/strong>In the \u221d \u2013 particle scattering experiment, when any other metal foil is used instead of gold, the observation would remain the same. This is because the structure of an atom, when considered individually, remains the same.<\/span><\/p>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong><span style=\"color: #ff0000;\">Questions<\/span> <\/strong><\/span><\/p>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>1. Name the three subatomic particles of an atom.<br \/>\n<\/strong><strong>Answer &#8211; <\/strong>An atom consists of three subatomic particles:<\/span><\/p>\n<ul style=\"text-align: justify;\">\n<li><span style=\"color: #000000;\">Protons \u00a0\u2013 Positively charged<\/span><\/li>\n<li><span style=\"color: #000000;\">Electrons \u2013 Negatively charged<\/span><\/li>\n<li><span style=\"color: #000000;\">Neutrons \u2013 Neutral in nature (no charge)<\/span><\/li>\n<\/ul>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>2. Helium atom has an atomic mass of 4 u and two protons in its nucleus. How many neutrons does it have?<br \/>\n<\/strong><strong>Answer &#8211;<br \/>\n<\/strong>Atomic mass of helium atom = 4u, 2 protons in helium nucleus<br \/>\nAtomic mass = number of protons + number of neutrons<br \/>\n4 = 2 + number of neutrons<br \/>\nNumber of neutrons = 4 \u2013 2 = 2<br \/>\nHence, Helium has 2 neutrons.<\/span><\/p>\n<p style=\"text-align: justify;\"><span style=\"color: #ff0000;\"><strong>Questions<\/strong><\/span><\/p>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>1. Write the distribution of electrons in Carbon and Sodium atoms.<br \/>\n<\/strong><strong>Answer &#8211;\u00a0 <\/strong>Atomic number of Carbon = 6<\/span><br \/>\n<span style=\"color: #000000;\">Therefore,\u00a0number of electrons in Carbon = 6<\/span><\/p>\n<ul>\n<li aria-level=\"1\"><span style=\"color: #000000;\">2\u00a0of them are held in\u00a0K Shell\u00a0(as K Shell can hold max 2 electrons)<\/span><\/li>\n<li aria-level=\"1\"><span style=\"color: #000000;\">4\u00a0of them are held in\u00a0L Shell\u00a0(as L Shell can hold max 8 electrons)<\/span><\/li>\n<\/ul>\n<p><span style=\"color: #000000;\">So, K Shell &#8211; 2 and L Shell &#8211; 4<\/span><\/p>\n<p><span style=\"color: #000000;\">Atomic number of Sodium = 11<\/span><br \/>\n<span style=\"color: #000000;\">Therefore,\u00a0number of electrons in Sodium = 11<\/span><\/p>\n<ul>\n<li aria-level=\"1\"><span style=\"color: #000000;\">2\u00a0of them are held in\u00a0K Shell\u00a0(as K Shell can hold max 2 electrons)<\/span><\/li>\n<li aria-level=\"1\"><span style=\"color: #000000;\">8\u00a0of them are held in\u00a0L Shell\u00a0(as L Shell can hold max 8 electrons)<\/span><\/li>\n<\/ul>\n<p><span style=\"color: #000000;\">Remaining 1 is held in M Shell <\/span><br \/>\n<span style=\"color: #000000;\">So, K Shell &#8211; 2, L Shell &#8211; 8 and M Shell &#8211; 1<\/span><\/p>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>2. If the K and L shells of an atom are full, then what would be the total number of electrons in the atom?<br \/>\n<\/strong><strong>Answer &#8211;<br \/>\n<\/strong>K shell can hold 2 electrons.<br \/>\nL shell can hold 8 electrons.<br \/>\nHence, when both the shells are full, the total number of electrons present in the atom = 2 + 8 = 10 electrons.<\/span><\/p>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong><span style=\"color: #ff0000;\">Questions<\/span> <\/strong><\/span><\/p>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>1. How will you find the valency of chlorine, sulphur and magnesium?<br \/>\n<\/strong><strong>Answer &#8211;<br \/>\n<\/strong><strong>Chlorine<\/strong><br \/>\nAtomic number of chlorine = 17<\/span><br \/>\n<span style=\"color: #000000;\">Electronic configuration of chlorine is &#8211; 2, 8, 7<\/span><br \/>\n<span style=\"color: #000000;\">Number of valence electrons = 7<\/span><br \/>\n<span style=\"color: #000000;\">Since atom has\u00a07 valence electrons\u00a0it is\u00a0easier for the atom to gain 1 electron\u00a0to achieve an\u00a0octet.<\/span><br \/>\n<span style=\"color: #000000;\">Valency of atoms gaining 1 electron = 1<\/span><br \/>\n<span style=\"color: #000000;\">Therefore,\u00a0Valency of chlorine = 1<\/span><\/p>\n<p><span style=\"color: #000000;\"><strong>Sulphur<br \/>\n<\/strong>Atomic number of Sulphur = 16<\/span><br \/>\n<span style=\"color: #000000;\">Electronic configuration of sulphur is &#8211; 2, 8, 6<\/span><br \/>\n<span style=\"color: #000000;\">Number of valence electrons = 6<\/span><br \/>\n<span style=\"color: #000000;\">Since the atom has\u00a06 valence electrons\u00a0it is\u00a0easier for it to gain 2 electrons\u00a0to achieve an\u00a0octet.<\/span><br \/>\n<span style=\"color: #000000;\">Valency of atoms gaining 2 electrons = 2<\/span><br \/>\n<span style=\"color: #000000;\">Therefore,\u00a0Valency of sulphur = 2<\/span><\/p>\n<p><span style=\"color: #000000;\"><strong>Magnesium<br \/>\n<\/strong>Atomic number of magnesium = 12<\/span><br \/>\n<span style=\"color: #000000;\">Electronic configuration of magnesium is &#8211; 2, 8, 2<\/span><br \/>\n<span style=\"color: #000000;\">Number of valence electrons = 2<\/span><br \/>\n<span style=\"color: #000000;\">Since the atom has\u00a02 valence electrons\u00a0it is\u00a0easier for it to lose 2 electrons\u00a0to achieve an\u00a0octet\u00a0.<\/span><br \/>\n<span style=\"color: #000000;\">Valency of atoms losing 2 electrons = 2<\/span><br \/>\n<span style=\"color: #000000;\">Therefore,\u00a0Valency of magnesium = 2<\/span><\/p>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong><span style=\"color: #ff0000;\">Questions<\/span> <\/strong><\/span><\/p>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>1. If the number of electrons in an atom is 8 and the number of protons is also 8, then<br \/>\n<\/strong><strong>(i) <\/strong>What is the atomic number of the atom? and<strong><br \/>\n<\/strong><strong>(ii) <\/strong>What is the charge on the atom?<br \/>\n<strong>Answer &#8211;<br \/>\n<\/strong>Number of electrons = 8<br \/>\nNumber of protons = 8<br \/>\n<strong>(i)<\/strong> Atomic number is equal to the number of protons in one atom. Since this atom contains 8 orotons, so the atomic is 8.<br \/>\n<strong>(ii)<\/strong> This atom contains an equal number of positively charged and negatively charged electrons (8 each), so it has no overall charge. That is, the charge on this atom is 0 (zero).<br \/>\n<\/span><\/p>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>2. With the help of the given table, find out the mass number of oxygen and sulphur atom.<br \/>\n<\/strong><strong>Table: Composition of Atoms of the First Eighteen Elements with Electron Distribution in Various Shells.<br \/>\n<\/strong><\/span><\/p>\n<table>\n<tbody>\n<tr>\n<td style=\"text-align: center;\" rowspan=\"2\"><span style=\"color: #000000;\"><strong>Name of Element<\/strong><\/span><\/td>\n<td style=\"text-align: center;\" rowspan=\"2\"><span style=\"color: #000000;\"><strong>Symbol<\/strong><\/span><\/td>\n<td style=\"text-align: center;\" rowspan=\"2\"><span style=\"color: #000000;\"><strong>Atomic Number<\/strong><\/span><\/td>\n<td style=\"text-align: center;\" rowspan=\"2\"><span style=\"color: #000000;\"><strong>Number of protons<\/strong><\/span><\/td>\n<td style=\"text-align: center;\" rowspan=\"2\"><span style=\"color: #000000;\"><strong>Number of Neutrons<\/strong><\/span><\/td>\n<td style=\"text-align: center;\" rowspan=\"2\"><span style=\"color: #000000;\"><strong>Number of Electrons<\/strong><\/span><\/td>\n<td style=\"text-align: center;\" colspan=\"4\"><span style=\"color: #000000;\"><strong>Distribution of Electrons<\/strong><\/span><\/td>\n<td style=\"text-align: center;\" rowspan=\"2\"><span style=\"color: #000000;\"><strong>Valency<\/strong><\/span><\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\"><strong>K<\/strong><\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\"><strong>L<\/strong><\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\"><strong>M<\/strong><\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\"><strong>N<\/strong><\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"color: #000000;\">Hydrogen<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">H<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">1<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">1<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">1<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">1<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">1<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"color: #000000;\">Helium<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">He<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">2<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">2<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">2<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">2<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">2<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">0<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"color: #000000;\">Lithium<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">Li<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">3<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">3<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">4<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">3<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">2<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">1<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">1<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"color: #000000;\">Beryllium<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">Be<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">4<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">4<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">5<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">4<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">2<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">2<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">2<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"color: #000000;\">Boron<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">B<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">5<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">5<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">6<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">5<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">2<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">3<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">3<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"color: #000000;\">Carbon<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">C<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">6<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">6<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">6<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">6<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">2<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">4<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">4<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"color: #000000;\">Nitrogen<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">N<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">7<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">7<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">7<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">7<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">2<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">5<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">3<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"color: #000000;\">Oxygen<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">O<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">8<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">8<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">8<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">8<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">2<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">6<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">2<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"color: #000000;\">Fluorine<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">F<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">9<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">9<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">10<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">9<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">2<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">7<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">1<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"color: #000000;\">Neon<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">Ne<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">10<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">10<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">10<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">10<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">2<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">8<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">0<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"color: #000000;\">Sodium<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">Na<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">11<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">11<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">12<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">11<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">2<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">8<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">1<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">1<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"color: #000000;\">Magnesium<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">Mg<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">12<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">12<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">12<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">12<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">2<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">8<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">2<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">2<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"color: #000000;\">Aluminium<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">Al<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">13<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">13<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">14<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">13<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">2<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">8<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">3<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">3<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"color: #000000;\">Silicon<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">Si<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">14<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">14<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">14<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">14<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">2<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">8<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">4<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">4<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"color: #000000;\">Phosphorus<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">P<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">15<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">15<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">16<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">15<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">2<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">8<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">5<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">3.5<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"color: #000000;\">Sulphur<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">S<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">16<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">16<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">16<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">16<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">2<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">8<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">6<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">2<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"color: #000000;\">Chlorine<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">Cl<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">17<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">17<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">18<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">17<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">2<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">8<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">7<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">1<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"color: #000000;\">Argon<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">Ar<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">18<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">18<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">22<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">18<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">2<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">8<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">8<\/span><\/td>\n<td style=\"text-align: center;\"><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">0<\/span><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>Answer &#8211;<br \/>\n<\/strong><strong>(a)<\/strong> To find the mass number of Oxygen,<br \/>\nNumber of protons = 8<br \/>\nNumber of neutrons = 8<br \/>\nAtomic number = 8<br \/>\nAtomic mass number = Number of protons + number of neutrons = 8 + 8 = 16<br \/>\nTherefore, the mass number of oxygen = 16<\/span><\/p>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>(b)<\/strong> To find the mass number of Sulphur,<br \/>\nNumber of protons = 16<br \/>\nNumber of neutrons = 16<br \/>\nAtomic number = 16<br \/>\nAtomic mass number = Number of protons + number of neutrons = 16 + 16 = 32<\/span><\/p>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong><span style=\"color: #ff0000;\">Questions<\/span> <\/strong><\/span><\/p>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>1. For the symbols H, D and T, tabulate three subatomic particles found in each of them.<br \/>\n<\/strong><strong>Answer &#8211; <\/strong>The following table depicts the subatomic particles in Hydrogen (H), Deuterium (D), and Tritium(T).<\/span><\/p>\n<div class=\"table-responsive\" style=\"text-align: justify;\">\n<table class=\"table table-bordered\">\n<tbody>\n<tr>\n<td><span style=\"color: #000000;\"><strong>Isotope<\/strong><\/span><\/td>\n<td><span style=\"color: #000000;\"><strong>Symbol<\/strong><\/span><\/td>\n<td><span style=\"color: #000000;\"><strong>Mass no.<\/strong><\/span><\/td>\n<td><span style=\"color: #000000;\"><strong>Atomic no.<\/strong><\/span><\/td>\n<td><span style=\"color: #000000;\"><strong>No. of electrons<\/strong><\/span><\/td>\n<td><span style=\"color: #000000;\"><strong>No. of protons<\/strong><\/span><\/td>\n<td><span style=\"color: #000000;\"><strong>No. of neutrons<\/strong><\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"color: #000000;\">Hydrogen<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">H<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">1<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">1<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">1<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">1<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">0<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"color: #000000;\">Deuterium<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">D<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">2<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">1<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">1<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">1<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">1<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"color: #000000;\">Tritium<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">T<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">3<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">1<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">1<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">1<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">2<\/span><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>2. Write the electronic configuration of any one pair of isotopes and isobar.<br \/>\n<\/strong><strong>Answer &#8211;<br \/>\n<\/strong><strong>(a) Isotopes :<\/strong> Isotopes are atoms which have the same number of protons, but the number of neutrons differs. This leads to the variation in mass number too.<br \/>\n<strong>Example &#8211; <\/strong>Carbon molecule exists as <sub>6<\/sub>C<sup>12<\/sup>\u00a0and\u00a0<sub>6<\/sub>C<sup>14<\/sup>, but when their electronic configuration is noticed, both have K-2; L-4<\/span><\/p>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>(b) Isobars :<\/strong> Isobars are atoms which have the same mass number but differ in atomic number. The electronic configuration of an isobar pair is as follows:<br \/>\n<strong>Example &#8211;<\/strong> Electronic configuration of <sub>20<\/sub>Ca<sup>40<\/sup>\u00a0\u2013 K-2; L-8; M-8; N- 2<br \/>\nElectronic configuration of\u00a0<sub>18<\/sub>Ar<sup>40<\/sup> \u2013 K-2; L-8; M-8\u00a0<\/span><\/p>\n<p style=\"text-align: center;\"><span style=\"text-decoration: underline; color: #ff0000;\"><span style=\"font-size: 14pt;\"><strong>Exercise<\/strong><\/span><\/span><\/p>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>1. Compare the properties of electrons, protons and neutrons. <\/strong><br \/>\n<strong>Answer &#8211;<\/strong><\/span><\/p>\n<div class=\"table-responsive\" style=\"text-align: justify;\">\n<table class=\"table table-bordered\">\n<tbody>\n<tr>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\"><strong>Property<\/strong><\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\"><strong>Electrons<\/strong><\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\"><strong>Protons<\/strong><\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\"><strong>Neutrons<\/strong><\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"color: #000000;\">Charge<\/span><\/td>\n<td><span style=\"color: #000000;\">Negatively charged<\/span><\/td>\n<td><span style=\"color: #000000;\">Positively charged<\/span><\/td>\n<td><span style=\"color: #000000;\">No charge.<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"color: #000000;\">Location<\/span><\/td>\n<td><span style=\"color: #000000;\">Located outside the nucleus<\/span><\/td>\n<td><span style=\"color: #000000;\">Located within the nucleus<\/span><\/td>\n<td><span style=\"color: #000000;\">Located inside the nucleus of an atom<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"color: #000000;\">Weight<\/span><\/td>\n<td><span style=\"color: #000000;\">Mass is negligible<\/span><\/td>\n<td><span style=\"color: #000000;\">1 a.m.u<\/span><\/td>\n<td><span style=\"color: #000000;\">1 a.m.u<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"color: #000000;\">Affinity<\/span><\/td>\n<td><span style=\"color: #000000;\">Attracted towards positively charged<\/span><\/td>\n<td><span style=\"color: #000000;\">Attracted towards negatively charged<\/span><\/td>\n<td><span style=\"color: #000000;\">Do not get attracted to any charged particle<\/span><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>2. What are the limitations of J.J.Thomson\u2019s model of the atom?<\/strong><br \/>\n<strong>Answer &#8211; <\/strong>Limitations of J.J Thomson&#8217;s model of an atom:<\/span><\/p>\n<ul style=\"text-align: justify;\">\n<li><span style=\"color: #000000;\">The results of Rutherford&#8217;s alpha particle scattering experiment could not be explained by Thomson&#8217;s model.<\/span><\/li>\n<li><span style=\"color: #000000;\">His concept has a number of significant flaws, one of which being the absence of any experimental data.<\/span><\/li>\n<li><span style=\"color: #000000;\">He was unable to explain why atoms are stable.<\/span><\/li>\n<\/ul>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>3. What are the limitations of Rutherford\u2019s model of the atom?<br \/>\n<\/strong><strong>Answer &#8211;\u00a0<\/strong>Limitations of Rutherford\u2019s model of the atom:<\/span><\/p>\n<ul style=\"text-align: justify;\">\n<li aria-level=\"1\"><span style=\"color: #000000;\">Electrons revolve around the nucleus in a circular path.<\/span><\/li>\n<li aria-level=\"1\"><span style=\"color: #000000;\">This is not possible because, if a particle follows a circular orbit, it will undergo acceleration (due to change in velocity as a result of continuous change in direction in a circular path).<\/span><\/li>\n<li aria-level=\"1\"><span style=\"color: #000000;\">During acceleration, charged particles radiate and lose energy.<\/span><\/li>\n<li aria-level=\"1\"><span style=\"color: #000000;\">After losing all energy, the charged electron will ultimately fall into the nucleus.<\/span><\/li>\n<li aria-level=\"1\"><span style=\"color: #000000;\">This would make the atom very unstable.<\/span><\/li>\n<li aria-level=\"1\"><span style=\"color: #000000;\">But we know that atoms are actually stable.<\/span><\/li>\n<li aria-level=\"1\"><span style=\"color: #000000;\">Hence, there was a flaw in Rutherford&#8217;s model of an atom.<\/span><\/li>\n<\/ul>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>4. Describe Bohr\u2019s model of the atom.<br \/>\n<\/strong><strong>Answer &#8211;\u00a0<\/strong>The present concept of atom was given by Neils Bohr. The bohr\u2019s model of atom can be described as follows:<\/span><\/p>\n<ul style=\"text-align: justify;\">\n<li><span style=\"color: #000000;\">An atom holds the nucleus at the centre.<\/span><\/li>\n<li><span style=\"color: #000000;\">Negatively charged electrons revolve around the nucleus.<\/span><\/li>\n<li><span style=\"color: #000000;\">The atoms in it contain distinct orbits of electrons.<\/span><\/li>\n<li><span style=\"color: #000000;\">Electrons do not radiate energy when they are in their orbits.<\/span><\/li>\n<li><span style=\"color: #000000;\">The distinct orbits are named K, L, M, and N orbits. Numbers used to denote them are n=1, 2, 3, 4<\/span><\/li>\n<\/ul>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-4996\" src=\"https:\/\/theexampillar.com\/ncert\/wp-content\/uploads\/2023\/02\/NCERT-Solutions-Class-9-Science-Ch-4-Q-03.png\" alt=\"NCERT Class 9 Solutions Maths\" width=\"544\" height=\"318\" srcset=\"https:\/\/theexampillar.com\/ncert\/wp-content\/uploads\/2023\/02\/NCERT-Solutions-Class-9-Science-Ch-4-Q-03.png 544w, https:\/\/theexampillar.com\/ncert\/wp-content\/uploads\/2023\/02\/NCERT-Solutions-Class-9-Science-Ch-4-Q-03-300x175.png 300w, https:\/\/theexampillar.com\/ncert\/wp-content\/uploads\/2023\/02\/NCERT-Solutions-Class-9-Science-Ch-4-Q-03-480x281.png 480w\" sizes=\"auto, (max-width: 544px) 100vw, 544px\" \/><\/span><\/p>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>5. Compare all the proposed models of an atom given in this chapter.<br \/>\n<\/strong><strong>Answer &#8211;<\/strong><\/span><\/p>\n<table style=\"border-collapse: collapse; width: 100%;\">\n<tbody>\n<tr>\n<td style=\"width: 33.3333%;\"><span style=\"color: #000000;\"><strong>Thomson<\/strong><\/span><\/td>\n<td style=\"width: 33.3333%;\"><span style=\"color: #000000;\"><strong>Rutherford<\/strong><\/span><\/td>\n<td style=\"width: 33.3333%;\"><span style=\"color: #000000;\"><strong>Bohr<\/strong><\/span><\/td>\n<\/tr>\n<tr>\n<td style=\"width: 33.3333%;\"><span style=\"color: #000000;\">Sphere is positively charged.<\/span><\/td>\n<td style=\"width: 33.3333%;\"><span style=\"color: #000000;\">The nucleus is at the centre and is positively charged, holding the entire mass.<\/span><\/td>\n<td style=\"width: 33.3333%;\"><span style=\"color: #000000;\">Nucleus is present at the centre and is positively charged<\/span><\/td>\n<\/tr>\n<tr>\n<td style=\"width: 33.3333%;\"><span style=\"color: #000000;\">Electrons are negatively charged and scattered all through the inside of the sphere.<\/span><\/td>\n<td style=\"width: 33.3333%;\"><span style=\"color: #000000;\">Electrons are negatively charged, revolving in a well-defined path<\/span><\/td>\n<td style=\"width: 33.3333%;\"><span style=\"color: #000000;\">Electrons are negatively charged, revolving around but do not radiate energy.<\/span><\/td>\n<\/tr>\n<tr>\n<td style=\"width: 33.3333%;\"><span style=\"color: #000000;\">Positively charged = negatively charged<br \/>\n<\/span><\/td>\n<td style=\"width: 33.3333%;\"><span style=\"color: #000000;\">In comparison with the nucleus, the size of the atom is very large.<\/span><\/td>\n<td style=\"width: 33.3333%;\"><span style=\"color: #000000;\">The distinct orbits are labelled as K, L, M, and N<\/span><\/td>\n<\/tr>\n<tr>\n<td style=\"width: 33.3333%;\"><span style=\"color: #000000;\">The net charge in the atom is zero.<br \/>\n<\/span><\/td>\n<td style=\"width: 33.3333%;\"><span style=\"color: #000000;\">Force of attraction of the electrons towards the nucleus is balanced by centrifugal force acting away from it. As a result, electrons are not drawn close to the nucleus.<\/span><\/td>\n<td style=\"width: 33.3333%;\"><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong style=\"text-align: justify;\">6. Summarise the rules for writing of distribution of electrons in various shells for the first eighteen elements.<br \/>\nAnswer &#8211;\u00a0<\/strong>The rules for writing of distribution of electrons in various shells for the first eighteen elements are:<\/span><\/p>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>1.<\/strong> The maximum number of electrons present in a shell is formula\u20142n<sup>2<br \/>\n<\/sup>n = orbit number i.e., 1, 2, 3<\/span><br \/>\n<span style=\"color: #000000;\">Maximum number of electrons in different shells are:<\/span><\/p>\n<ul style=\"text-align: justify;\">\n<li><span style=\"color: #000000;\">K shell n = 1 2n<sup>2<\/sup>\u00a0\u21d2 2(1)<sup>2<\/sup> = 2<\/span><\/li>\n<li><span style=\"color: #000000;\">L shell n = 2 2n<sup>2<\/sup>\u00a0\u21d2 2(2)<sup>2<\/sup> = 8<\/span><\/li>\n<li><span style=\"color: #000000;\">M shell n = 3 2n<sup>2<\/sup>\u00a0\u21d2 2(3)<sup>2<\/sup> = 18<\/span><\/li>\n<li><span style=\"color: #000000;\">N shell n = 4 2n<sup>2<\/sup>\u00a0\u21d2 2(4)<sup>2<\/sup>\u00a0= 32<\/span><\/li>\n<\/ul>\n<div class=\" col-md-8\" style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>2.<\/strong> The maximum number of electrons that can be accommodated in the outermost orbit is 8.<\/span><\/div>\n<div class=\" col-md-8\" style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>3.<\/strong> Electrons are not accommodated in a given shell unless the inner shells are filled. (Shells are filled step-wise).<\/span><\/div>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>7. Define valency by taking examples of silicon and oxygen.<br \/>\n<strong style=\"text-align: justify;\">Answer &#8211;\u00a0<\/strong><\/strong>Valency is the combining capacity of an atom.<\/span><br \/>\n<span style=\"color: #000000;\">Atomic number of oxygen = 8<\/span><br \/>\n<span style=\"color: #000000;\">Atomic number of silicon = 14<\/span><\/p>\n<table style=\"width: 50.5435%; border-collapse: collapse;\">\n<tbody>\n<tr>\n<td style=\"width: 31.9979%;\"><\/td>\n<td style=\"width: 4.89976%; text-align: center;\"><span style=\"color: #000000;\">K<\/span><\/td>\n<td style=\"width: 3.81472%; text-align: center;\"><span style=\"color: #000000;\">L<\/span><\/td>\n<td style=\"width: 3.68643%; text-align: center;\"><span style=\"color: #000000;\">M<\/span><\/td>\n<\/tr>\n<tr>\n<td style=\"width: 31.9979%;\"><span style=\"color: #000000;\">Electronic configuration of oxygen <\/span><\/td>\n<td style=\"width: 4.89976%; text-align: center;\"><span style=\"color: #000000;\">2<\/span><\/td>\n<td style=\"width: 3.81472%; text-align: center;\"><span style=\"color: #000000;\">6<\/span><\/td>\n<td style=\"width: 3.68643%; text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<\/tr>\n<tr>\n<td style=\"width: 31.9979%;\"><span style=\"color: #000000;\">Electronic configuration of silicon <\/span><\/td>\n<td style=\"width: 4.89976%; text-align: center;\"><span style=\"color: #000000;\">2<\/span><\/td>\n<td style=\"width: 3.81472%; text-align: center;\"><span style=\"color: #000000;\">8<\/span><\/td>\n<td style=\"width: 3.68643%; text-align: center;\"><span style=\"color: #000000;\">4<\/span><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<div class=\" col-md-8\" style=\"text-align: justify;\"><span style=\"color: #000000;\">In the atoms of oxygen the valence electrons are 6 (i.e., electrons in the outermost shell). To fill the orbit, 2 electrons are required. In the atom of silicon, the valence electrons are 4. To fill this orbit 4 electrons are required. <\/span><br \/>\n<span style=\"color: #000000;\">Hence, the combining capacity of oxygen is 2 and of silicon is 4. <\/span><br \/>\n<span style=\"color: #000000;\">i.e., Valency of oxygen = 2<\/span><br \/>\n<span style=\"color: #000000;\">Valency of silicon = 4<\/span><\/div>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>8. <\/strong><strong>Explain with examples:<br \/>\n(i) Atomic number<\/strong><\/span><br \/>\n<span style=\"color: #000000;\"><strong>(ii) Mass number,<\/strong><\/span><br \/>\n<span style=\"color: #000000;\"><strong>(iii) Isotopes and<\/strong><\/span><br \/>\n<span style=\"color: #000000;\"><strong>(iv) Isobars.<\/strong><\/span><br \/>\n<span style=\"color: #000000;\"><strong>Give any two uses of isotopes.<br \/>\n<\/strong><strong><strong style=\"text-align: justify;\">Answer &#8211;\u00a0<\/strong><br \/>\n<\/strong><b>(i) Atomic number &#8211; <\/b>The atomic number of an element is equal to the number of protons in the nucleus of its atom. e.g., Oxygen has 6 protons hence atomic no. = 6.<\/span><\/p>\n<p style=\"text-align: justify;\"><b style=\"color: #000000;\">(ii) Maas number &#8211; <\/b><span style=\"color: #000000;\">The total number of protons and neutrons present in one atom of an element is known as its mass number. For example, one atom of sodium element contains 11 protons and 12 neutrons. Hence, the mass number of sodium is 11 + 12 = 23. Similarly, a normal carbon atom has 6 protons and 6 neutrons, so the mass number of carbon is 6 + 6 = 12.<\/span><\/p>\n<p style=\"text-align: justify;\"><strong style=\"color: #000000;\">(iii) Isotopes &#8211; <\/strong><span style=\"color: #000000;\">Atoms of same element with same atomic number but different mass number are called isotopes of that element. For example, Hydrogen has three isotopes, protium (H<\/span><sup style=\"color: #000000;\">1<\/sup><sub style=\"color: #000000;\">1<\/sub><span style=\"color: #000000;\">), deuterium (H<\/span><sup style=\"color: #000000;\">2<\/sup><sub style=\"color: #000000;\">1<\/sub><span style=\"color: #000000;\">\u00a0or D<\/span><sup style=\"color: #000000;\">2<\/sup><sub style=\"color: #000000;\">1<\/sub><span style=\"color: #000000;\">) and tritium (H<\/span><sup style=\"color: #000000;\">3<\/sup><sub style=\"color: #000000;\">1<\/sub><span style=\"color: #000000;\">\u00a0or T<\/span><sup style=\"color: #000000;\">3<\/sup><sub style=\"color: #000000;\">1<\/sub><span style=\"color: #000000;\">). Many elements consist of a mixture of isotopes. Each isotope of an element is a pure substance. The chemical properties of isotopes are similar but their physical properties are different.<\/span><\/p>\n<p style=\"text-align: justify;\"><strong style=\"color: #000000;\">(iv) Isobars &#8211; <\/strong><span style=\"color: #000000;\">Atoms of different elements which have the same mass number but have different atomic numbers are called isobars. For example, calcium, atomic number-20 and argon, atomic number 18 are isobars. Both these elements have same mass number which is equal to 40. Therefore, the total number of nucleons is the same in both the elements.<\/span><\/p>\n<div class=\"row\" style=\"text-align: justify;\">\n<p><span style=\"color: #000000;\"><strong>Uses of Isotopes:<\/strong>\u00a0 Isotopes of some elements have special properties makes them useful in various fields. For example, <\/span><br \/>\n<span style=\"color: #000000;\"><strong>1.<\/strong> An isotope of uranium is used as a fuel in nuclear reactors. <\/span><br \/>\n<span style=\"color: #000000;\"><strong>2.<\/strong> An isotope of cobalt is used in the treatment of cancer. <\/span><br \/>\n<span style=\"color: #000000;\"><strong>3.<\/strong> An isotope of iodine is used in the treatment of goitre.<\/span><\/p>\n<\/div>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>9. Na+ has completely filled K and L shells. Explain.<br \/>\n<\/strong><strong>Answer &#8211;\u00a0<\/strong>A sodium ion Na+, has 10 electrons in it. Now, the maximum capacity of K shell is 2 electrons and that of L shell is 8 electrons. Taken together, the maximum capacity of K and L shells is 2 + 8 = 10 electrons. A sodium ion Na+ has completely filled K and L shells because its 10 electrons can completely fill up K and L shells.<\/span><\/p>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>10. If bromine is available in the form of, say, two isotopes <sub>35<\/sub>Br<sup>79<\/sup> (49.7%) <sub>35<\/sub>Br<sup>81<\/sup> (5,3%) calculate the average atomic mass of bromine atom.<br \/>\n<\/strong><strong>Answer &#8211;<br \/>\n<\/strong>The mass of <sub>35<\/sub>Br<sup>79<\/sup> isotope is 79 u and its abundance is 49.7%.<\/span><br \/>\n<span style=\"color: #000000;\">The mass of <sub>35<\/sub>Br<sup>81<\/sup> \u00a0isotope is 81 u and its abundance is 50.3%.<\/span><br \/>\n<span style=\"color: #000000;\">So, Average atomic mass of bromine = 79 \u00d7 <img decoding=\"async\" src=\"https:\/\/latex.codecogs.com\/gif.latex?\\frac{49.7}{100}&amp;space;+81&amp;space;\\times&amp;space;\\frac{50.3}{100}\" alt=\"\\frac{49.7}{100} +81 \\times \\frac{50.3}{100}\" align=\"absmiddle\" \/><\/span><\/p>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\">= <img decoding=\"async\" src=\"https:\/\/latex.codecogs.com\/gif.latex?\\frac{3926.3}{100}+\\frac{4074.3}{100}\" alt=\"\\frac{3926.3}{100}+\\frac{4074.3}{100}\" align=\"absmiddle\" \/><br \/>\n= 39.263 + 40.743<\/span><br \/>\n<span style=\"color: #000000;\">= 80.006<\/span><br \/>\n<span style=\"color: #000000;\">= 80u<\/span><br \/>\n<span style=\"color: #000000;\">Thus, the average atomic mass of bromine is 80 u.<\/span><\/p>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>11. The average atomic mass of a sample of an element X is 16.2 u. What are the percentages of isotopes <sub>8<\/sub>X<sup>16<\/sup> \u00a0and <sub>8<\/sub>X<sup>18<\/sup> \u00a0in the sample.<br \/>\n<\/strong><strong>Answer &#8211;\u00a0<\/strong>In order to solve this problem, we will have to suppose that the percentage of one of the isotopes in the sample is x, so that the percentage of the other isotope in the sample will be (100 &#8211; x). Now:<\/span><br \/>\n<span style=\"color: #000000;\">The mass of <sub>8<\/sub>X<sup>16<\/sup> isotope is 16u. Suppose its percentage in the sample is x%.<\/span><br \/>\n<span style=\"color: #000000;\">The mass of <sub>8<\/sub>X<sup>18 <\/sup>isotope is 18 u. Its percentage in the sample will be (100 &#8211; x)%.<\/span><br \/>\n<span style=\"color: #000000;\">So, Average atomic mass of X = 16 \u00d7 <img decoding=\"async\" src=\"https:\/\/latex.codecogs.com\/gif.latex?\\frac{X}{100}&amp;space;+&amp;space;18&amp;space;\\times&amp;space;\\frac{(100-X)}{100}\" alt=\"\\frac{X}{100} + 18 \\times \\frac{(100-X)}{100}\" align=\"absmiddle\" \/><\/span><br \/>\n<span style=\"color: #000000;\">But the average atomic mass of X has been given to be 16.2 u. Therefore,<\/span><\/p>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\">16.2 = 16 \u00d7 <img decoding=\"async\" src=\"https:\/\/latex.codecogs.com\/gif.latex?\\frac{X}{100}&amp;space;+&amp;space;18&amp;space;\\times&amp;space;\\frac{(100-X)}{100}\" alt=\"\\frac{X}{100} + 18 \\times \\frac{(100-X)}{100}\" align=\"absmiddle\" \/><\/span><br \/>\n<span style=\"color: #000000;\">16.2 = <img decoding=\"async\" src=\"https:\/\/latex.codecogs.com\/gif.latex?\\frac{16X&amp;space;+&amp;space;1800-18X}{100}\" alt=\"\\frac{16X + 1800-18X}{100}\" align=\"absmiddle\" \/> <\/span><br \/>\n<span style=\"color: #000000;\">16.2 \u00d7 100 = 1800 &#8211; 2X<\/span><br \/>\n<span style=\"color: #000000;\">2X = 1800 \u2013 1620<\/span><br \/>\n<span style=\"color: #000000;\">2X = 180<\/span><br \/>\n<span style=\"color: #000000;\">X = 180\/2<\/span><br \/>\n<span style=\"color: #000000;\">X = 90 <\/span><br \/>\n<span style=\"color: #000000;\">Thus, the percentage of the isotope <sub>8<\/sub>X<sup>16 <\/sup>in the sample is 90%. The percentage of the isotope <sub>8<\/sub>X<sup>18\u00a0 <\/sup>in the sample will be 100 \u2013 90 = 10%.<\/span><\/p>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>12. If Z = 3, what would be the valency of the element? Also name the element.<br \/>\n<\/strong><strong>Answer &#8211;\u00a0<\/strong>By Z = 3, we mean that the atomic number of the element is 3. Its electronic configuration is 2, 1. Hence, the valency of the element is 1 (since the outermost shell has only one electron).<br \/>\nTherefore, the element with Z = 3 is lithium (Li).<\/span><\/p>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>13. Composition of the nuclei of two atomic species X and Y is given as under:<br \/>\n<\/strong><\/span><\/p>\n<table style=\"width: 50%; border-collapse: collapse;\">\n<tbody>\n<tr>\n<td style=\"width: 25%;\"><\/td>\n<td style=\"width: 25%; text-align: center;\"><\/td>\n<td style=\"width: 25%; text-align: center;\"><span style=\"color: #000000;\">X<\/span><\/td>\n<td style=\"width: 25%; text-align: center;\"><span style=\"color: #000000;\">Y<\/span><\/td>\n<\/tr>\n<tr>\n<td style=\"width: 25%;\"><span style=\"color: #000000;\">Protons\u00a0<\/span><\/td>\n<td style=\"width: 25%; text-align: center;\"><span style=\"color: #000000;\">=\u00a0<\/span><\/td>\n<td style=\"width: 25%; text-align: center;\"><span style=\"color: #000000;\">6<\/span><\/td>\n<td style=\"width: 25%; text-align: center;\"><span style=\"color: #000000;\">6<\/span><\/td>\n<\/tr>\n<tr>\n<td style=\"width: 25%;\"><span style=\"color: #000000;\">Neutrons <\/span><\/td>\n<td style=\"width: 25%; text-align: center;\"><span style=\"color: #000000;\">=\u00a0<\/span><\/td>\n<td style=\"width: 25%; text-align: center;\"><span style=\"color: #000000;\">6<\/span><\/td>\n<td style=\"width: 25%; text-align: center;\"><span style=\"color: #000000;\">8<\/span><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>Give the mass numbers of X and Y. What is the relation between the two species?<br \/>\n<\/strong><strong>Answer &#8211;\u00a0 <\/strong>Mass number = No. of protons + No. of neutrons <\/span><br \/>\n<span style=\"color: #000000;\">So, Mass number of X = 6 + 6 = 12 <\/span><br \/>\n<span style=\"color: #000000;\">Mass number of Y = 6 + 8 = 14<\/span><br \/>\n<span style=\"color: #000000;\">Thus, the mass number of X is 12 and that of Y is 14<\/span><\/p>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>14. <\/strong><strong>For the following statements, write T for True and F for False.<\/strong><\/span><br \/>\n<span style=\"color: #000000;\"><strong>(a)<\/strong> J.J. Thomson proposed that the nucleus of an atom contains only nucleons.<\/span><br \/>\n<span style=\"color: #000000;\"><strong>(b)<\/strong> A neutron is formed by an electron and a proton combining together. Therefore, it is neutral.<\/span><br \/>\n<span style=\"color: #000000;\"><strong>(c)<\/strong> The mass of an electron is about 1\/2000 times that of proton.<\/span><br \/>\n<span style=\"color: #000000;\"><strong>(d)<\/strong> An isotope of iodine is used for making tincture iodine, which is used as a medicine.<\/span><br \/>\n<span style=\"color: #000000;\"><strong>Answer &#8211;<br \/>\n<\/strong><strong>(a)<\/strong> J.J. Thomson proposed that the nucleus of an atom contains only nucleons. <strong>(False)<\/strong><br \/>\n<strong>(b)<\/strong> A neutron is formed by an electron and a proton combining together. Therefore, it is neutral. <strong>(False)<\/strong><br \/>\n<strong>(c)<\/strong> The mass of an electron is about 1\/2000 times that of proton. <strong>(True)<\/strong><br \/>\n<strong>(d)<\/strong> An isotope of iodine is used for making tincture iodine, which is used as a medicine. <strong>(False)<\/strong><\/span><\/p>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>15. Rutherford&#8217;s alpha-particle scattering experiment was responsible for the discovery of:<br \/>\n(a)<\/strong> Atomic nucleuse<\/span><br \/>\n<span style=\"color: #000000;\"><strong>(b)<\/strong> Electrone<\/span><br \/>\n<span style=\"color: #000000;\"><strong>(c)<\/strong> Protone<\/span><br \/>\n<span style=\"color: #000000;\"><strong>(d)<\/strong> Neutron<\/span><br \/>\n<span style=\"color: #000000;\"><strong>Answer &#8211;\u00a0<\/strong>(a) Atomic nucleus<\/span><\/p>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>16. <\/strong><strong>Isotopes of an element have :<br \/>\n<\/strong><strong>(a)<\/strong> the same physical properties<\/span><br \/>\n<span style=\"color: #000000;\"><strong>(b) <\/strong>different chemical properties<\/span><br \/>\n<span style=\"color: #000000;\"><strong>(c)<\/strong> different number of neutrons<\/span><br \/>\n<span style=\"color: #000000;\"><strong>(d)<\/strong> different atomic numbers<\/span><br \/>\n<span style=\"color: #000000;\"><strong>Answer &#8211;\u00a0<\/strong>(c) different number of neutrons.<\/span><\/p>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>17. Number of valence electrons in Cl- ion are:<br \/>\n<\/strong>(a) 16<\/span><br \/>\n<span style=\"color: #000000;\">(b) 8<\/span><br \/>\n<span style=\"color: #000000;\">(c) 17<\/span><br \/>\n<span style=\"color: #000000;\">(d) 18<\/span><br \/>\n<span style=\"color: #000000;\"><strong>Answer &#8211;\u00a0<\/strong>(b) 8<\/span><\/p>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>18. Which of the following is a correct electronic configuration of sodium?<br \/>\n<\/strong>(a) 2, 8 <\/span><br \/>\n<span style=\"color: #000000;\">(b) 8, 2, 1<\/span><br \/>\n<span style=\"color: #000000;\">(c) 2, 1, 8 <\/span><br \/>\n<span style=\"color: #000000;\">(d) 2, 8,1<\/span><br \/>\n<span style=\"color: #000000;\"><strong>Answer &#8211;\u00a0<\/strong>(d) 2, 8, 1<\/span><\/p>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>19. Complete the following table:<br \/>\n<\/strong><\/span><\/p>\n<table>\n<tbody>\n<tr>\n<td><span style=\"color: #000000;\"><b>Atomic Number<\/b><\/span><\/td>\n<td><span style=\"color: #000000;\"><b>Mass Number<\/b><\/span><\/td>\n<td><span style=\"color: #000000;\"><b>Number of Neutrons<\/b><\/span><\/td>\n<td><span style=\"color: #000000;\"><b>Number of Protons<\/b><\/span><\/td>\n<td><span style=\"color: #000000;\"><b>Number of Electrons<\/b><\/span><\/td>\n<td><span style=\"color: #000000;\"><b>Name of the Atomic Species<\/b><\/span><\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">9<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">10<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">10<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">32<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">Sulphure<\/span><\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">24<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">12<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">2<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">1<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">1<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">0<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">1<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">0<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">&#8211;<\/span><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><strong>Answer &#8211; <\/strong>The following table depicts the missing data:<br \/>\nAtomic number (Z) = Number of protons<br \/>\nMass number = Number of neutrons + atomic number<br \/>\n(or)<br \/>\nMass number (A) = Number of neutrons + number of neutrons<\/span><\/p>\n<table>\n<tbody>\n<tr>\n<td><span style=\"color: #000000;\"><b>Atomic Number<\/b><\/span><\/td>\n<td><span style=\"color: #000000;\"><b>Mass Number<\/b><\/span><\/td>\n<td><span style=\"color: #000000;\"><b>Number of Neutrons<\/b><\/span><\/td>\n<td><span style=\"color: #000000;\"><b>Number of Protons<\/b><\/span><\/td>\n<td><span style=\"color: #000000;\"><b>Number of Electrons<\/b><\/span><\/td>\n<td><span style=\"color: #000000;\"><b>Name of the Atomic Species<\/b><\/span><\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">9<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">19<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">10<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">9<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">9<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">Fluorine<\/span><\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">16<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">32<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">16<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">16<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">16<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">Sulphure<\/span><\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">12<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">24<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">12<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">12<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">12<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">Magnesium<\/span><\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">1<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">2<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">1<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">1<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">1<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">Deuterium<\/span><\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">1<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">1<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">0<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">1<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">1<\/span><\/td>\n<td style=\"text-align: center;\"><span style=\"color: #000000;\">Protium<\/span><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<div class=\"table-responsive\"><\/div>\n<div>\n<p><a href=\"https:\/\/theexampillar.com\/ncert\/ncert-solutions-class-9-science\/\" target=\"_blank\" rel=\"noopener\"><b><i>Go Back To Chapters<\/i><\/b><\/a><\/p>\n<p>&nbsp;<\/p>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>NCERT Solutions Class 9 Science\u00a0 The NCERT Solutions in English Language for Class 9 Science Chapter &#8211; 4 (Structure of the Atom) has been provided here to help the students in solving the questions from this exercise. Chapter &#8211; 4 (Structure of the Atom) Questions 1. What are the canal rays? Answer &#8211;\u00a0Canal rays are [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[729],"tags":[730,738,739,733,5],"class_list":["post-4963","post","type-post","status-publish","format-standard","hentry","category-class-9-science","tag-class-9-ncert-solutions","tag-ncert-class-9-science-chapter-4-structure-of-the-atom","tag-ncert-solutions-class-9-science-chapter-4-in-english","tag-ncert-solutions-class-9-science-in-english","tag-ncert-solutions-in-english"],"yoast_head":"<!-- This site is optimized with the Yoast SEO Premium plugin v22.9 (Yoast SEO v27.3) - https:\/\/yoast.com\/product\/yoast-seo-premium-wordpress\/ -->\n<title>NCERT Solutions Class 9 Science Chapter 4 Structure of the Atom | TheExamPillar NCERT<\/title>\n<meta name=\"description\" content=\"NCERT Solutions Class 9 Science\u00a0The NCERT Solutions in English Language for Class 9 Science Chapter - 4 (Structure of the Atom) has been provided here to help the students in solving the questions from this exercise.\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/theexampillar.com\/ncert\/ncert-solutions-class-9-science-chapter-4-structure-of-the-atom\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"NCERT Solutions Class 9 Science Chapter 4 Structure of the Atom\" \/>\n<meta property=\"og:description\" content=\"NCERT Solutions Class 9 Science\u00a0The NCERT Solutions in English Language for Class 9 Science Chapter - 4 (Structure of the Atom) has been provided here to help the students in solving the questions from this exercise.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/theexampillar.com\/ncert\/ncert-solutions-class-9-science-chapter-4-structure-of-the-atom\/\" \/>\n<meta property=\"og:site_name\" content=\"TheExamPillar NCERT\" \/>\n<meta property=\"article:published_time\" content=\"2023-03-16T07:22:22+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2023-03-28T06:14:47+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/theexampillar.com\/ncert\/wp-content\/uploads\/2023\/02\/NCERT-Solutions-Class-9-Science-Ch-4-Q-03.png\" \/>\n<meta name=\"author\" content=\"Admin\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:creator\" content=\"@exampillar\" \/>\n<meta name=\"twitter:site\" content=\"@exampillar\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"Admin\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"16 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\\\/\\\/theexampillar.com\\\/ncert\\\/ncert-solutions-class-9-science-chapter-4-structure-of-the-atom\\\/#article\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/theexampillar.com\\\/ncert\\\/ncert-solutions-class-9-science-chapter-4-structure-of-the-atom\\\/\"},\"author\":{\"name\":\"Admin\",\"@id\":\"https:\\\/\\\/theexampillar.com\\\/ncert\\\/#\\\/schema\\\/person\\\/521fbdbd2eb8621382a3096b5e3ecaf1\"},\"headline\":\"NCERT Solutions Class 9 Science Chapter 4 Structure of the Atom\",\"datePublished\":\"2023-03-16T07:22:22+00:00\",\"dateModified\":\"2023-03-28T06:14:47+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\\\/\\\/theexampillar.com\\\/ncert\\\/ncert-solutions-class-9-science-chapter-4-structure-of-the-atom\\\/\"},\"wordCount\":2839,\"commentCount\":0,\"publisher\":{\"@id\":\"https:\\\/\\\/theexampillar.com\\\/ncert\\\/#\\\/schema\\\/person\\\/521fbdbd2eb8621382a3096b5e3ecaf1\"},\"image\":{\"@id\":\"https:\\\/\\\/theexampillar.com\\\/ncert\\\/ncert-solutions-class-9-science-chapter-4-structure-of-the-atom\\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/theexampillar.com\\\/ncert\\\/wp-content\\\/uploads\\\/2023\\\/02\\\/NCERT-Solutions-Class-9-Science-Ch-4-Q-03.png\",\"keywords\":[\"Class 9 NCERT Solutions\",\"NCERT Class 9 Science Chapter 4 Structure of the Atom\",\"NCERT Solutions Class 9 Science Chapter 4 in English\",\"NCERT Solutions Class 9 Science in English\",\"NCERT Solutions in English\"],\"articleSection\":[\"Class 9 Science\"],\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"CommentAction\",\"name\":\"Comment\",\"target\":[\"https:\\\/\\\/theexampillar.com\\\/ncert\\\/ncert-solutions-class-9-science-chapter-4-structure-of-the-atom\\\/#respond\"]}]},{\"@type\":\"WebPage\",\"@id\":\"https:\\\/\\\/theexampillar.com\\\/ncert\\\/ncert-solutions-class-9-science-chapter-4-structure-of-the-atom\\\/\",\"url\":\"https:\\\/\\\/theexampillar.com\\\/ncert\\\/ncert-solutions-class-9-science-chapter-4-structure-of-the-atom\\\/\",\"name\":\"NCERT Solutions Class 9 Science Chapter 4 Structure of the Atom | TheExamPillar NCERT\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/theexampillar.com\\\/ncert\\\/#website\"},\"primaryImageOfPage\":{\"@id\":\"https:\\\/\\\/theexampillar.com\\\/ncert\\\/ncert-solutions-class-9-science-chapter-4-structure-of-the-atom\\\/#primaryimage\"},\"image\":{\"@id\":\"https:\\\/\\\/theexampillar.com\\\/ncert\\\/ncert-solutions-class-9-science-chapter-4-structure-of-the-atom\\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/theexampillar.com\\\/ncert\\\/wp-content\\\/uploads\\\/2023\\\/02\\\/NCERT-Solutions-Class-9-Science-Ch-4-Q-03.png\",\"datePublished\":\"2023-03-16T07:22:22+00:00\",\"dateModified\":\"2023-03-28T06:14:47+00:00\",\"description\":\"NCERT Solutions Class 9 Science\u00a0The NCERT Solutions in English Language for Class 9 Science Chapter - 4 (Structure of the Atom) has been provided here to help the students in solving the questions from this exercise.\",\"breadcrumb\":{\"@id\":\"https:\\\/\\\/theexampillar.com\\\/ncert\\\/ncert-solutions-class-9-science-chapter-4-structure-of-the-atom\\\/#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\\\/\\\/theexampillar.com\\\/ncert\\\/ncert-solutions-class-9-science-chapter-4-structure-of-the-atom\\\/\"]}]},{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\\\/\\\/theexampillar.com\\\/ncert\\\/ncert-solutions-class-9-science-chapter-4-structure-of-the-atom\\\/#primaryimage\",\"url\":\"https:\\\/\\\/theexampillar.com\\\/ncert\\\/wp-content\\\/uploads\\\/2023\\\/02\\\/NCERT-Solutions-Class-9-Science-Ch-4-Q-03.png\",\"contentUrl\":\"https:\\\/\\\/theexampillar.com\\\/ncert\\\/wp-content\\\/uploads\\\/2023\\\/02\\\/NCERT-Solutions-Class-9-Science-Ch-4-Q-03.png\",\"width\":544,\"height\":318,\"caption\":\"NCERT Class 9 Solutions Maths\"},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\\\/\\\/theexampillar.com\\\/ncert\\\/ncert-solutions-class-9-science-chapter-4-structure-of-the-atom\\\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\\\/\\\/theexampillar.com\\\/ncert\\\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"NCERT Solutions Class 9 Science Chapter 4 Structure of the Atom\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\\\/\\\/theexampillar.com\\\/ncert\\\/#website\",\"url\":\"https:\\\/\\\/theexampillar.com\\\/ncert\\\/\",\"name\":\"TheExamPillar NCERT\",\"description\":\"\",\"publisher\":{\"@id\":\"https:\\\/\\\/theexampillar.com\\\/ncert\\\/#\\\/schema\\\/person\\\/521fbdbd2eb8621382a3096b5e3ecaf1\"},\"alternateName\":\"NCERT Solution\",\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\\\/\\\/theexampillar.com\\\/ncert\\\/?s={search_term_string}\"},\"query-input\":{\"@type\":\"PropertyValueSpecification\",\"valueRequired\":true,\"valueName\":\"search_term_string\"}}],\"inLanguage\":\"en-US\"},{\"@type\":[\"Person\",\"Organization\"],\"@id\":\"https:\\\/\\\/theexampillar.com\\\/ncert\\\/#\\\/schema\\\/person\\\/521fbdbd2eb8621382a3096b5e3ecaf1\",\"name\":\"Admin\",\"image\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\\\/\\\/theexampillar.com\\\/ncert\\\/wp-content\\\/uploads\\\/2022\\\/07\\\/cropped-ExamPillar-PNG.png\",\"url\":\"https:\\\/\\\/theexampillar.com\\\/ncert\\\/wp-content\\\/uploads\\\/2022\\\/07\\\/cropped-ExamPillar-PNG.png\",\"contentUrl\":\"https:\\\/\\\/theexampillar.com\\\/ncert\\\/wp-content\\\/uploads\\\/2022\\\/07\\\/cropped-ExamPillar-PNG.png\",\"width\":512,\"height\":512,\"caption\":\"Admin\"},\"logo\":{\"@id\":\"https:\\\/\\\/theexampillar.com\\\/ncert\\\/wp-content\\\/uploads\\\/2022\\\/07\\\/cropped-ExamPillar-PNG.png\"},\"sameAs\":[\"https:\\\/\\\/theexampillar.com\\\/ncert\"],\"url\":\"https:\\\/\\\/theexampillar.com\\\/ncert\\\/author\\\/ncert_eng_vikram\\\/\"}]}<\/script>\n<!-- \/ Yoast SEO Premium plugin. -->","yoast_head_json":{"title":"NCERT Solutions Class 9 Science Chapter 4 Structure of the Atom | TheExamPillar NCERT","description":"NCERT Solutions Class 9 Science\u00a0The NCERT Solutions in English Language for Class 9 Science Chapter - 4 (Structure of the Atom) has been provided here to help the students in solving the questions from this exercise.","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/theexampillar.com\/ncert\/ncert-solutions-class-9-science-chapter-4-structure-of-the-atom\/","og_locale":"en_US","og_type":"article","og_title":"NCERT Solutions Class 9 Science Chapter 4 Structure of the Atom","og_description":"NCERT Solutions Class 9 Science\u00a0The NCERT Solutions in English Language for Class 9 Science Chapter - 4 (Structure of the Atom) has been provided here to help the students in solving the questions from this exercise.","og_url":"https:\/\/theexampillar.com\/ncert\/ncert-solutions-class-9-science-chapter-4-structure-of-the-atom\/","og_site_name":"TheExamPillar NCERT","article_published_time":"2023-03-16T07:22:22+00:00","article_modified_time":"2023-03-28T06:14:47+00:00","og_image":[{"url":"https:\/\/theexampillar.com\/ncert\/wp-content\/uploads\/2023\/02\/NCERT-Solutions-Class-9-Science-Ch-4-Q-03.png","type":"","width":"","height":""}],"author":"Admin","twitter_card":"summary_large_image","twitter_creator":"@exampillar","twitter_site":"@exampillar","twitter_misc":{"Written by":"Admin","Est. reading time":"16 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"Article","@id":"https:\/\/theexampillar.com\/ncert\/ncert-solutions-class-9-science-chapter-4-structure-of-the-atom\/#article","isPartOf":{"@id":"https:\/\/theexampillar.com\/ncert\/ncert-solutions-class-9-science-chapter-4-structure-of-the-atom\/"},"author":{"name":"Admin","@id":"https:\/\/theexampillar.com\/ncert\/#\/schema\/person\/521fbdbd2eb8621382a3096b5e3ecaf1"},"headline":"NCERT Solutions Class 9 Science Chapter 4 Structure of the Atom","datePublished":"2023-03-16T07:22:22+00:00","dateModified":"2023-03-28T06:14:47+00:00","mainEntityOfPage":{"@id":"https:\/\/theexampillar.com\/ncert\/ncert-solutions-class-9-science-chapter-4-structure-of-the-atom\/"},"wordCount":2839,"commentCount":0,"publisher":{"@id":"https:\/\/theexampillar.com\/ncert\/#\/schema\/person\/521fbdbd2eb8621382a3096b5e3ecaf1"},"image":{"@id":"https:\/\/theexampillar.com\/ncert\/ncert-solutions-class-9-science-chapter-4-structure-of-the-atom\/#primaryimage"},"thumbnailUrl":"https:\/\/theexampillar.com\/ncert\/wp-content\/uploads\/2023\/02\/NCERT-Solutions-Class-9-Science-Ch-4-Q-03.png","keywords":["Class 9 NCERT Solutions","NCERT Class 9 Science Chapter 4 Structure of the Atom","NCERT Solutions Class 9 Science Chapter 4 in English","NCERT Solutions Class 9 Science in English","NCERT Solutions in English"],"articleSection":["Class 9 Science"],"inLanguage":"en-US","potentialAction":[{"@type":"CommentAction","name":"Comment","target":["https:\/\/theexampillar.com\/ncert\/ncert-solutions-class-9-science-chapter-4-structure-of-the-atom\/#respond"]}]},{"@type":"WebPage","@id":"https:\/\/theexampillar.com\/ncert\/ncert-solutions-class-9-science-chapter-4-structure-of-the-atom\/","url":"https:\/\/theexampillar.com\/ncert\/ncert-solutions-class-9-science-chapter-4-structure-of-the-atom\/","name":"NCERT Solutions Class 9 Science Chapter 4 Structure of the Atom | TheExamPillar NCERT","isPartOf":{"@id":"https:\/\/theexampillar.com\/ncert\/#website"},"primaryImageOfPage":{"@id":"https:\/\/theexampillar.com\/ncert\/ncert-solutions-class-9-science-chapter-4-structure-of-the-atom\/#primaryimage"},"image":{"@id":"https:\/\/theexampillar.com\/ncert\/ncert-solutions-class-9-science-chapter-4-structure-of-the-atom\/#primaryimage"},"thumbnailUrl":"https:\/\/theexampillar.com\/ncert\/wp-content\/uploads\/2023\/02\/NCERT-Solutions-Class-9-Science-Ch-4-Q-03.png","datePublished":"2023-03-16T07:22:22+00:00","dateModified":"2023-03-28T06:14:47+00:00","description":"NCERT Solutions Class 9 Science\u00a0The NCERT Solutions in English Language for Class 9 Science Chapter - 4 (Structure of the Atom) has been provided here to help the students in solving the questions from this exercise.","breadcrumb":{"@id":"https:\/\/theexampillar.com\/ncert\/ncert-solutions-class-9-science-chapter-4-structure-of-the-atom\/#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/theexampillar.com\/ncert\/ncert-solutions-class-9-science-chapter-4-structure-of-the-atom\/"]}]},{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/theexampillar.com\/ncert\/ncert-solutions-class-9-science-chapter-4-structure-of-the-atom\/#primaryimage","url":"https:\/\/theexampillar.com\/ncert\/wp-content\/uploads\/2023\/02\/NCERT-Solutions-Class-9-Science-Ch-4-Q-03.png","contentUrl":"https:\/\/theexampillar.com\/ncert\/wp-content\/uploads\/2023\/02\/NCERT-Solutions-Class-9-Science-Ch-4-Q-03.png","width":544,"height":318,"caption":"NCERT Class 9 Solutions Maths"},{"@type":"BreadcrumbList","@id":"https:\/\/theexampillar.com\/ncert\/ncert-solutions-class-9-science-chapter-4-structure-of-the-atom\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/theexampillar.com\/ncert\/"},{"@type":"ListItem","position":2,"name":"NCERT Solutions Class 9 Science Chapter 4 Structure of the Atom"}]},{"@type":"WebSite","@id":"https:\/\/theexampillar.com\/ncert\/#website","url":"https:\/\/theexampillar.com\/ncert\/","name":"TheExamPillar NCERT","description":"","publisher":{"@id":"https:\/\/theexampillar.com\/ncert\/#\/schema\/person\/521fbdbd2eb8621382a3096b5e3ecaf1"},"alternateName":"NCERT Solution","potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/theexampillar.com\/ncert\/?s={search_term_string}"},"query-input":{"@type":"PropertyValueSpecification","valueRequired":true,"valueName":"search_term_string"}}],"inLanguage":"en-US"},{"@type":["Person","Organization"],"@id":"https:\/\/theexampillar.com\/ncert\/#\/schema\/person\/521fbdbd2eb8621382a3096b5e3ecaf1","name":"Admin","image":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/theexampillar.com\/ncert\/wp-content\/uploads\/2022\/07\/cropped-ExamPillar-PNG.png","url":"https:\/\/theexampillar.com\/ncert\/wp-content\/uploads\/2022\/07\/cropped-ExamPillar-PNG.png","contentUrl":"https:\/\/theexampillar.com\/ncert\/wp-content\/uploads\/2022\/07\/cropped-ExamPillar-PNG.png","width":512,"height":512,"caption":"Admin"},"logo":{"@id":"https:\/\/theexampillar.com\/ncert\/wp-content\/uploads\/2022\/07\/cropped-ExamPillar-PNG.png"},"sameAs":["https:\/\/theexampillar.com\/ncert"],"url":"https:\/\/theexampillar.com\/ncert\/author\/ncert_eng_vikram\/"}]}},"_links":{"self":[{"href":"https:\/\/theexampillar.com\/ncert\/wp-json\/wp\/v2\/posts\/4963","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/theexampillar.com\/ncert\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/theexampillar.com\/ncert\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/theexampillar.com\/ncert\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/theexampillar.com\/ncert\/wp-json\/wp\/v2\/comments?post=4963"}],"version-history":[{"count":5,"href":"https:\/\/theexampillar.com\/ncert\/wp-json\/wp\/v2\/posts\/4963\/revisions"}],"predecessor-version":[{"id":5404,"href":"https:\/\/theexampillar.com\/ncert\/wp-json\/wp\/v2\/posts\/4963\/revisions\/5404"}],"wp:attachment":[{"href":"https:\/\/theexampillar.com\/ncert\/wp-json\/wp\/v2\/media?parent=4963"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/theexampillar.com\/ncert\/wp-json\/wp\/v2\/categories?post=4963"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/theexampillar.com\/ncert\/wp-json\/wp\/v2\/tags?post=4963"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}