{"id":9018,"date":"2018-02-08T15:57:40","date_gmt":"2018-02-08T10:27:40","guid":{"rendered":"http:\/\/mycbseguide.com\/blog\/?p=9018"},"modified":"2019-03-05T15:53:25","modified_gmt":"2019-03-05T10:23:25","slug":"atoms-class-12-notes-physics","status":"publish","type":"post","link":"https:\/\/mycbseguide.com\/blog\/atoms-class-12-notes-physics\/","title":{"rendered":"Atoms Class 12 Notes Physics"},"content":{"rendered":"<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_76 counter-hierarchy ez-toc-counter ez-toc-grey ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">Table of Contents<\/p>\n<span class=\"ez-toc-title-toggle\"><a href=\"#\" class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" aria-label=\"Toggle Table of Content\"><span class=\"ez-toc-js-icon-con\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/span><\/a><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1 eztoc-toggle-hide-by-default' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/mycbseguide.com\/blog\/atoms-class-12-notes-physics\/#CBSE_Guide_Atoms_class_12_Notes_Physics\" >CBSE Guide Atoms class 12 Notes Physics<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/mycbseguide.com\/blog\/atoms-class-12-notes-physics\/#Class_12_Physics_notes_Chapter_12_Atoms\" >Class 12 Physics notes Chapter 12 Atoms<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/mycbseguide.com\/blog\/atoms-class-12-notes-physics\/#CBSE_Class_12_Physics_Revision_Notes_Chapter-12_Atoms\" >CBSE Class 12\u00a0Physics Revision Notes Chapter-12 Atoms<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/mycbseguide.com\/blog\/atoms-class-12-notes-physics\/#CBSE_Class_12_Revision_Notes_and_Key_Points\" >CBSE Class 12 Revision Notes and Key Points<\/a><\/li><\/ul><\/nav><\/div>\n<p><strong>CBSE Chapter 12 Atoms Class 12 Notes Physics<\/strong> in PDF are available for free download in myCBSEguide mobile app. The best app for CBSE students now provides Atoms class 12 Notes Physics latest chapter wise notes for quick preparation of CBSE board exams and school-based annual examinations. Class 12 Physics notes on chapter 12 Atoms are also available for download in CBSE Guide website.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"CBSE_Guide_Atoms_class_12_Notes_Physics\"><\/span><strong>CBSE Guide Atoms class 12 Notes Physics<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>CBSE guide notes are the comprehensive notes which covers the latest syllabus of CBSE and NCERT. It includes all the topics given in NCERT class 12 Physics textbook. Users can download CBSE guide quick revision notes from myCBSEguide mobile app and my CBSE guide website.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Class_12_Physics_notes_Chapter_12_Atoms\"><\/span><strong>Class 12 Physics notes Chapter 12 Atoms<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Download CBSE class 12th revision notes for chapter 12 Atoms in PDF format for free. Download revision notes for Atoms class 12 Notes and score high in exams. These are the Atoms class 12 Notes prepared by team of expert teachers. The revision notes help you revise the whole chapter 12 in minutes. Revision notes in exam days is one of the best tips recommended by teachers during exam days.<\/p>\n<p style=\"text-align: center;\"><strong><a class=\"button\" href=\"https:\/\/mycbseguide.com\/downloads\/cbse-class-12-physics\/1251\/cbse-revision-notes\/7\/\">Download Revision Notes as PDF<\/a><\/strong><\/p>\n<h2><span class=\"ez-toc-section\" id=\"CBSE_Class_12_Physics_Revision_Notes_Chapter-12_Atoms\"><\/span><strong>CBSE Class 12\u00a0Physics Revision Notes Chapter-12 Atoms<br \/>\n<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<ul>\n<li><strong>Thomson\u2019s Model of an Atom: <\/strong>An atom consists of positively charged matter in which the negatively charged electrons are uniformly embedded like plums in a pudding. This model could not explain scattering of alpha-particles through thin foils and hence discarded.<\/li>\n<li><strong>Rutherford\u2019s Model of an Atom: \u00a0<\/strong>Geiger and Marsden in their experiment on scattering of alpha-particles found that most of the alpha-particles passed undeviated through thin foils but some of them were scattered through very large angles.<\/li>\n<\/ul>\n<p>From the results of these experiments, Rutherford proposed the following model of an atom:-<\/p>\n<p>a)\u00a0\u00a0An atom consists of a small and massive central core in which the entire positive charge and almost the whole mass of the atom are concentrated. This core is called the nucleus.<\/p>\n<p>b)\u00a0\u00a0The nucleus occupies a very small space as compared to the size of the atom.<\/p>\n<p>c)\u00a0\u00a0The atom is surrounded by a suitable number of electros so that their total negative charge is equal to the total positive charge on the nucleus and the atom as a whole is electrically neutral.<\/p>\n<p>d) The electrons revolve around the nucleus in various orbits just as planets revolve around the sun.<\/p>\n<p>e)\u00a0\u00a0The centripetal force required for their revolution is provided by the electrostatic attraction between the electrons and the nucleus.<\/p>\n<ul>\n<li><strong>Draw-back of Rutherford Model: <\/strong>This model could not explain instability of the atom because according to classical electromagnetic theory the electron revolving around the nucleus must continuously radiate energy in the form of electromagnetic radiation and hence it should fall into the nucleus.<\/li>\n<li><strong>Distance of Closest Approach: <\/strong>When an alpha-particle of mass m and velocity v moves directly towards a nucleus of atomic number Z, its initial energy E, which is just the kinetic energy K gets completely converted into potential energy U at stopping point. This stopping point happens to be at a distance of closest approach d from the nucleus.<\/li>\n<\/ul>\n<p><span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\"><span class=\"math-tex cke_widget_element\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi?E=\\frac{1}{2}m{{v}^{2}}=\\frac{1}{4\\pi {{\\varepsilon }_{0}}}\\frac{2eZe}{d}=\\frac{2Z{{e}^{2}}}{4\\pi {{\\varepsilon }_{0}}d}d=\\frac{2Z{{e}^{2}}}{4\\pi {{\\varepsilon }_{0}}k}\" \/><\/span><\/span><\/p>\n<p>Hence, <span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\"><span class=\"math-tex cke_widget_element\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi?d=\\frac{2Z{{e}^{2}}}{4\\pi {{\\varepsilon }_{0}}K}\" \/><\/span><\/span><\/p>\n<ul>\n<li><strong>Impact Parameter:<\/strong><\/li>\n<\/ul>\n<p>a)\u00a0\u00a0It is defined as the perpendicular distance of the velocity of the alpha-particle from the centre\u00a0of the nucleus, when it is far away from the atom.<\/p>\n<p>b) The shape of the trajectory of the scattered alpha-particle depends on the impact parameter b and the nature of the potential field.<\/p>\n<p>c)\u00a0\u00a0Rutherford deduced the following relationship between the impact parameter b and the scattering angle <span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\"><span class=\"math-tex cke_widget_element\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi?\\theta\" \/><\/span><\/span>:-<\/p>\n<p><span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\"><span class=\"math-tex cke_widget_element\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi?\\begin{align} &amp;amp; b=\\frac{1}{4\\pi {{\\varepsilon }_{0}}}.\\frac{Z{{e}^{2}}\\cot \\frac{\\theta }{2}}{E} \\\\ &amp;amp; =\\frac{1}{4\\pi {{\\varepsilon }_{0}}}\\frac{Z{{e}^{2}}\\cot \\frac{\\theta }{2}}{\\frac{1}{2}m{{v}^{2}}} \\\\ \\end{align}\" \/><\/span><\/span><\/p>\n<ul>\n<li><strong>Quantisation or Discretisation: <\/strong>The quantization or discretisation of a physical quantity means that it cannot have any arbitrary value but can change only to take certain specific value.<\/li>\n<\/ul>\n<ul>\n<li><strong>Bohr\u2019s Model for the Hydrogen Atom: <\/strong>Basic postulates:-<\/li>\n<\/ul>\n<p><strong>a)\u00a0\u00a0Nuclear concept:<\/strong> An atom consists of a small massive centre\u00a0called nucleus around which planetary electrons revolve. The centripetal force required for their rotation is provided by the electrostatic attraction between the electrons and the nucleus.<\/p>\n<p><strong>b)\u00a0\u00a0Quantum condition:<\/strong> Of all the possible circular orbits allowed by the classical theory, the electrons are permitted to circulate only in such orbits in which the angular momentum of an electron is an integral multiple of\u00a0<span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\"><span class=\"math-tex cke_widget_element\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi?{h \\over {2\\pi }}\" \/><\/span><\/span>, h being Planck\u2019s constant.<\/p>\n<p>&nbsp;<\/p>\n<p>where n is called principal quantum number.<\/p>\n<p><strong>c)\u00a0\u00a0Stationary orbits:<\/strong> While revolving in the permissible orbits, an electron does not radiate energy. These non-radiating orbits are called stationary orbits.<\/p>\n<p><strong>d)\u00a0\u00a0Frequency condition:<\/strong> An atom can emit or absorb radiation in the form of discrete energy photons only\u00a0when an electron jumps from a higher to a lower orbit or from a lower to a higher orbit. If E<sub>1<\/sub> and E<sub>2<\/sub> are the energies associated with these permitted orbits then the frequency \u00a0of the emitted\/absorbed radiation is,<\/p>\n<p><span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\"><span class=\"math-tex cke_widget_element\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi?hv={{E}_{2}}-{{E}_{1}}\" \/><\/span><\/span><\/p>\n<p>e)\u00a0\u00a0Radius of the orbit of an electron in hydrogen atom is, <span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\"><span class=\"math-tex cke_widget_element\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi?r=\\frac{{{e}^{2}}}{4\\pi {{\\varepsilon }_{0}}m{{v}^{2}}}\" \/><\/span><\/span><\/p>\n<p>f)\u00a0\u00a0Kinetic energy K &amp; electrostatic potential energy U of the electron in hydrogen atom:-<\/p>\n<p><span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\"><span class=\"math-tex cke_widget_element\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi?K=\\frac{1}{2}m{{v}^{2}}=\\frac{{{e}^{2}}}{8\\pi {{\\varepsilon }_{0}}r}\" \/><\/span><\/span><\/p>\n<p><span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\"><span class=\"math-tex cke_widget_element\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi?U=-\\frac{{{e}^{2}}}{4\\pi {{\\varepsilon }_{0}}r}\" \/><\/span><\/span><\/p>\n<p>g)\u00a0\u00a0Total energy E of the electron in hydrogen atom:-<\/p>\n<p><span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\"><span class=\"math-tex cke_widget_element\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi?E=K+U=-\\frac{{{e}^{2}}}{8\\pi {{\\varepsilon }_{0}}r}\" \/><\/span><\/span><\/p>\n<p>h) \u00a0Speed of an electron in the n<sup>th<\/sup> orbit is,<\/p>\n<p>&nbsp;<\/p>\n<p>Where <span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\"><span class=\"math-tex cke_widget_element\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi?\\alpha =\\frac{2\\pi k{{e}^{2}}}{ch}\" \/><\/span><\/span>\u00a0is fine structure constant.<\/p>\n<p>i)\u00a0\u00a0Energy of an electron in n<sup>th<\/sup> orbit is,<\/p>\n<p><span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\"><span class=\"math-tex cke_widget_element\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi?{{E}_{n}}=\\frac{2{{\\pi }^{2}}m{{k}^{2}}{{Z}^{2}}{{e}^{4}}}{{{n}^{2}}{{h}^{2}}}=-\\frac{13.6}{{{n}^{2}}}eV\" \/><\/span><\/span><\/p>\n<ul>\n<li><strong>Failure of Bohr\u2019s Model: <\/strong><\/li>\n<\/ul>\n<p>a) \u00a0This model is applicable only to hydrogen-like atoms and fails in case of higher atoms.<\/p>\n<p>b)\u00a0\u00a0It could not explain the fine structure of the spectral lines in the spectrum of hydrogen\u00a0atom.<\/p>\n<ul>\n<li><strong>Energy Level Diagram: <\/strong>It is a diagram in which the energies of the different stationary states of an atom are represented by parallel horizontal lines, drawn according to some suitable energy scale.<\/li>\n<li><strong>Spectral Series of Hydrogen Atom: <\/strong>Whenever an electron in hydrogen atom makes a transition from a higher energy level n<sub>2<\/sub> to a lower energy level n<sub>1<\/sub>, the difference of energy appears in the form of a photon of frequency <span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\"><span class=\"math-tex cke_widget_element\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi?\\nu\" \/><\/span><\/span>\u00a0is given by-<\/li>\n<\/ul>\n<p><span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\"><span class=\"math-tex cke_widget_element\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi?v=\\frac{2{{\\pi }^{2}}m{{k}^{2}}{{e}^{2}}}{{{h}^{2}}}\\left[ \\frac{1}{n_{1}^{2}}-\\frac{1}{n_{2}^{2}} \\right]\" \/><\/span><\/span><\/p>\n<ul>\n<li><strong>Different Spectral Series of Hydrogen Atom:<\/strong><\/li>\n<\/ul>\n<p>These are as follows:<\/p>\n<p>a)\u00a0\u00a0Lyman Series. Here n<sub>2<\/sub> = 2, 3, 4,\u2026..and n<sub>1<\/sub> = 1. This series lies in the ultraviolet region.<\/p>\n<p>b)\u00a0\u00a0Balmer Series. Here n<sub>2<\/sub>= 3, 4, 5,\u2026. and n<sub>1<\/sub> = 2. This series lies in the visible region.<\/p>\n<p>c)\u00a0\u00a0Paschen Series. Here n<sub>2<\/sub>= 4, 5, 6,\u2026..and n<sub>1<\/sub> = 3. This series lies in the infrared region.<\/p>\n<p>d) \u00a0Brackett Series. Here n<sub>2<\/sub>= 5, 6, 7,\u2026..and n<sub>1<\/sub> = 4. This series lies in the infrared region.<\/p>\n<p>e)\u00a0\u00a0Pfund Series. Here n<sub>2<\/sub>= 6, 7, 8,\u2026. and n<sub>1<\/sub>= 5. This series lies in the infrared region.<\/p>\n<ul>\n<li><strong>Excitation Energy: <\/strong>It is defined as the energy required by an electron of an atom to jump from its ground state to any one of its existed state.<\/li>\n<li><strong>Ionisation Energy<\/strong>: It is defined as the energy required to remove an electron from an atom, i.e., the energy required to take an electron from its ground state to the outermost orbit (n = <span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\"><span class=\"math-tex cke_widget_element\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi?\\infty\" \/><\/span><\/span>)<\/li>\n<li><strong>Excitation Potential: <\/strong>It is the accelerating potential which gives sufficient energy to a bombarding electron, so to excite the target atom by raising one of its electrons from an inner to and outer orbit.<\/li>\n<li><strong>Ionisation Potential: <\/strong>It is the accelerating potential which gives to bombarding electron, sufficient energy to ionise the target atom by knocking one of its electrons completely out of the atom.<\/li>\n<li><strong>De Broglie\u2019s Hypothesis: <\/strong>The electrons having a wavelength <span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\"><span class=\"math-tex cke_widget_element\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi?\\lambda = {h \\over {mv}}\" \/><\/span><\/span>\u00a0gave an explanation for Bohr\u2019s quantised orbits by bringing in the wave-particle duality. The orbits correspond to circular standing waves in which the circumference of the orbit equals a whole number of wavelengths.<\/li>\n<\/ul>\n<ul>\n<li><strong>MASER:-<\/strong><\/li>\n<\/ul>\n<p>a) \u00a0Maser stands for \u2018Microwave\u00a0Amplification by Stimulated Emission of Radiation\u2019.<\/p>\n<p>b)\u00a0\u00a0It is simply a device for producing a highly intense, monochromatic coherent and collimated beam of microwaves.<\/p>\n<ul>\n<li><strong>LASER:-<\/strong><\/li>\n<\/ul>\n<p>a)\u00a0\u00a0It stand for \u2018Light Amplification by Stimulated Emission of Radiation.<\/p>\n<p>b)\u00a0\u00a0Itis a device used to produce highly intense strong monochromatic coherent and collimated beam of light.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"CBSE_Class_12_Revision_Notes_and_Key_Points\"><\/span><strong>CBSE Class 12 Revision Notes and Key Points<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Atoms class 12 Notes. CBSE quick revision note for class-12 Physics, Chemistry, Math\u2019s, Biology and other subject are very helpful to revise the whole syllabus during exam days. The revision notes covers all important formulas and concepts given in the chapter. Even if you wish to have an overview of a chapter, quick revision notes are here to do if for you. These notes will certainly save your time during stressful exam days.<\/p>\n<ul>\n<li><a href=\"http:\/\/mycbseguide.com\/downloads\/cbse-class-12-physics\/1251\/cbse-revision-notes\/7\/\">Physics<\/a><\/li>\n<li><a href=\"http:\/\/mycbseguide.com\/downloads\/cbse-class-12-chemistry\/1267\/cbse-revision-notes\/7\/\">Chemistry<\/a><\/li>\n<li><a href=\"http:\/\/mycbseguide.com\/downloads\/cbse-class-12-mathematics\/1284\/cbse-revision-notes\/7\/\">Mathematics<\/a><\/li>\n<li><a href=\"http:\/\/mycbseguide.com\/downloads\/cbse-class-12-biology\/1298\/cbse-revision-notes\/7\/\">Biology<\/a><\/li>\n<li><a href=\"http:\/\/mycbseguide.com\/downloads\/cbse-class-12-accountancy\/1315\/cbse-revision-notes\/7\/\">Accountancy<\/a><\/li>\n<li><a href=\"http:\/\/mycbseguide.com\/downloads\/cbse-class-12-economics\/1327\/cbse-revision-notes\/7\/\">Economics<\/a><\/li>\n<li><a href=\"http:\/\/mycbseguide.com\/downloads\/cbse-class-12-business-studies\/1727\/cbse-revision-notes\/7\/\">Business Studies<\/a><\/li>\n<li><a href=\"http:\/\/mycbseguide.com\/downloads\/cbse-class-12-computer-science\/1851\/cbse-revision-notes\/7\/\">Computer Science<\/a><\/li>\n<li><a href=\"http:\/\/mycbseguide.com\/downloads\/cbse-class-12-informatics-practices\/1873\/cbse-revision-notes\/7\/\">Informatics Practices<\/a><\/li>\n<li><a href=\"http:\/\/mycbseguide.com\/downloads\/cbse-class-12-english-core\/1855\/cbse-revision-notes\/7\/\">English Core<\/a><\/li>\n<li><a href=\"http:\/\/mycbseguide.com\/downloads\/cbse-class-12-history\/1869\/cbse-revision-notes\/7\/\">History<\/a><\/li>\n<li><a href=\"http:\/\/mycbseguide.com\/downloads\/cbse-class-12-physical-education\/1877\/cbse-revision-notes\/7\/\">Physical Education<\/a><\/li>\n<\/ul>\n<p>To download Atoms class 12 Notes, sample paper for class 12 Physics, Chemistry, Biology, History, Political Science, Economics, Geography, Computer Science, Home Science, Accountancy, Business Studies and Home Science; do check myCBSEguide app or website. myCBSEguide provides sample papers with solution, test papers for chapter-wise practice, NCERT solutions, NCERT Exemplar solutions, quick revision notes for ready reference, CBSE guess papers and CBSE important question papers. Sample Paper all are made available through\u00a0<a href=\"https:\/\/play.google.com\/store\/apps\/details?id=in.techchefs.MyCBSEGuide&amp;referrer=utm_source%3Dmycbse_bottom%26utm_medium%3Dtext%26utm_campaign%3Dmycbseads\"><strong>the best app for CBSE students<\/strong><\/a>\u00a0and myCBSEguide website.<\/p>\n<ul>\n<li><a href=\"https:\/\/mycbseguide.com\/blog\/electric-charges-fields-class-12-notes-physics\/\">Electric Charges and Fields class 12 Notes Physics<\/a><\/li>\n<li class=\"entry-title\"><a href=\"https:\/\/mycbseguide.com\/blog\/electrostatic-potential-capacitance-class-12-notes-physics\/\">Electrostatic Potential and Capacitance class 12 Notes Physics<\/a><\/li>\n<li class=\"entry-title\"><a href=\"https:\/\/mycbseguide.com\/blog\/current-electricity-class-12-notes-physics\/\">Current Electricity class 12 Notes Physics<\/a><\/li>\n<li class=\"entry-title\"><a href=\"https:\/\/mycbseguide.com\/blog\/moving-charges-magnetism-class-12-notes-physics\/\">Moving Charges and Magnetism class 12 Notes Physics<\/a><\/li>\n<li class=\"entry-title\"><a href=\"https:\/\/mycbseguide.com\/blog\/magnetism-matter-class-12-notes-physics\/\">Magnetism and Matter class 12 Notes Physics<\/a><\/li>\n<li class=\"entry-title\"><a href=\"https:\/\/mycbseguide.com\/blog\/electromagnetic-induction-class-12-notes-physics\/\">Electromagnetic Induction class 12 Notes Physics<\/a><\/li>\n<li class=\"entry-title\"><a href=\"https:\/\/mycbseguide.com\/blog\/alternating-current-class-12-notes-physics\/\">Alternating Current class 12 Notes Physics<\/a><\/li>\n<li class=\"entry-title\"><a href=\"https:\/\/mycbseguide.com\/blog\/electromagnetic-waves-class-12-notes-physics\/\">Electromagnetic Waves class 12 Notes Physics<\/a><\/li>\n<li class=\"entry-title\"><a href=\"https:\/\/mycbseguide.com\/blog\/ray-optics-and-optical-class-12-note-physics\/\">Ray Optics and Optical class 12 Notes Physics<\/a><\/li>\n<li class=\"entry-title\"><a href=\"https:\/\/mycbseguide.com\/blog\/wave-optics-class-12-notes-physics\/\">Wave Optics class 12 Notes Physics<\/a><\/li>\n<li class=\"entry-title\"><a href=\"https:\/\/mycbseguide.com\/blog\/dual-nature-radiation-matter-class-12-notes-physics\/\">Dual Nature of Radiation and Matter class 12 Notes Physics<\/a><\/li>\n<li class=\"entry-title\"><a href=\"https:\/\/mycbseguide.com\/blog\/atoms-class-12-notes-physics\/\">Atoms class 12 Notes Physics<\/a><\/li>\n<li class=\"entry-title\"><a href=\"https:\/\/mycbseguide.com\/blog\/nuclei-class-12-notes-physics\/\">Nuclei class 12 Notes Physics<\/a><\/li>\n<li class=\"entry-title\"><a href=\"https:\/\/mycbseguide.com\/blog\/electronic-devices-class-12-notes-physics\/\">Electronic Devices class 12 Notes Physics<\/a><\/li>\n<li class=\"entry-title\"><a href=\"https:\/\/mycbseguide.com\/blog\/communication-systems-class-12-notes-physics\/\">Communication Systems class 12 Notes Physics<\/a><\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>CBSE Chapter 12 Atoms Class 12 Notes Physics in PDF are available for free download in myCBSEguide mobile app. The best app for CBSE students now provides Atoms class 12 Notes Physics latest chapter wise notes for quick preparation of CBSE board exams and school-based annual examinations. Class 12 Physics notes on chapter 12 Atoms &#8230; <a title=\"Atoms Class 12 Notes Physics\" class=\"read-more\" href=\"https:\/\/mycbseguide.com\/blog\/atoms-class-12-notes-physics\/\" aria-label=\"More on Atoms Class 12 Notes Physics\">Read more<\/a><\/p>\n","protected":false},"author":2,"featured_media":8891,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[48,456],"tags":[493,457,150,458,426,240],"class_list":["post-9018","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-cbse-class-12","category-revision-notes","tag-atoms","tag-cbse-notes","tag-cbse-notes-and-key-points","tag-physics-notes","tag-quick-revision","tag-quick-revision-notes"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v26.0 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>Atoms Class 12 Notes Physics | myCBSEguide<\/title>\n<meta name=\"description\" content=\"Atoms class 12 Notes Physics chapter 12 in PDF format for free download. 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