Structure of Atom
Chapter Revision Structure of Atom Class 9 1.The nucleons are I. Protons and electrons II. Neutrons and electrons III. Protons and neutrons IV. None of these 2. The isotope deuterium of hydrogen has I. No neutrons and one proton II. One neutrons and two protons III. One electron and two neutron IV. One proton and one neutron 3. The electrons present in the outermost shell are called I. Valency electrons II. Octate electrons III. Duplet electrons IV. Valence electrons 4. An alpha particle contains I. 4 positive charge and 2 mass unit II. 2 positive charge and 4 mass unit III. 2 positive charge and 2 mass unit IV. 4 positive charge and 4 mass unit 5. The atomic number of sodium is 11 and its mass number is 23. It has I. 11 neutrons and 12 protons II. 12 protons and 11 electrons III. 11 electrons and 12 neutrons IV. 12 electrons and 11 neutrons 6. The electronic configuration of chlorine is I. 2,7 II. 2,8,8,7 III. 2,8,7 IV. 2,7,8 7. The isotope used to remove the brain tumours...