{"id":2263,"date":"2023-05-03T01:23:52","date_gmt":"2023-05-03T01:23:52","guid":{"rendered":"https:\/\/vartmaaninstitutesirsa.com\/?page_id=2263"},"modified":"2024-03-14T15:15:36","modified_gmt":"2024-03-14T15:15:36","slug":"chapter-13-nuclei","status":"publish","type":"page","link":"https:\/\/vartmaaninstitutesirsa.com\/index.php\/chapter-13-nuclei\/","title":{"rendered":"Chapter 13 Nuclei"},"content":{"rendered":"

Chapter 13 Nuclei<\/h1>\n
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Chapter\u201313: Nuclei Composition and size of nucleus, nuclear force, Mass-energy relation, mass defect; binding energy per nucleon and its variation with mass number; nuclear fission, nuclear fusion.<\/span><\/p>\n

14 Composition of a Nucleus:<\/span><\/strong><\/p>\n

After the Rutherford \u03b1-ray scatterings experiment two theories of<\/span>composition of nucleus were proposed which are as follow.<\/span><\/p>\n

Proton electron hypothesis:-<\/span><\/strong><\/p>\n

According to this hypothesis a nucleus is consist of all protons and some of electrons. Some electrons lie inside the nucleus and some revolve around the nucleus.<\/span>This theory failed due to:<\/span><\/p>\n

\uf0ad<\/span>By this theory we cannot predict the position of electron in an atom.<\/span><\/em><\/p>\n

\uf0ad<\/span>The stability of atom con not is explained by this theory<\/span><\/em>.<\/span><\/p>\n

Proton\u2013Neutron Hypothesis:<\/span><\/strong><\/p>\n

After the discovering of neutron by Chadwick, Heisenberg proposed proton-neutron hypothesis in 1932. According to this theory a nucleus is consist of Z number of protons and (A-Z) number of neutrons. Electrons equal to protons revolve around the nucleus in circular orbits.<\/span><\/p>\n

Symbol of an atom<\/span>\"\"<\/p>\n

Here an atom may be represented by X, the atomic number is represented by Z and atomic mass is represented by A.\u00a0<\/span><\/p>\n

As<\/span>\"\"<\/p>\n

i.e.<\/span>\"\"<\/p>\n

15 Some Terms Related to Composition of A Nucleus:<\/span><\/strong><\/p>\n