Q.1 What was the model of an atom proposed by Thomson?
Q.2 What is the nature of charge on electrons?
Q.3 What are canal rays ?
Q.4 State the nature of the constituents of canal rays.
Q.5 Who discovered the nucleus of the atom?
Q.6 What is the charge on alpha particles ?
Q.3 Which observation of Rutherford’s scattering experiment established the presence large empty space in atom?
Q.7 What is the nature of charge on nucleus of atom?
Q.8 Who discovered neutron ?
Q.9 Why is the relative mass of an electron is taken as negligible ?
Q.10 Give the actual masses of electron & proton in kg?
Q.11 What are nucleons?
Q.12 The mass number of an element is 18. It contains 7 electrons .What is the number of
Q.13 An atom contains 3 protons , 3 electrons and 4 neutrons .
i) What is its atomic number ? ii) What is its mass number?
Q.14 An element is represented by . Give the number of electrons and neutrons in it. 3115P
Q.15 What happens when an electron jumps from lower to higher energy level?
Q.16 Which energy shell is nearest to the nucleus of an atom?
Q.17 Which energy shell has higher energy L or N ?
Q.18 An atoms has atomic number 13. What would be its configuration.
Q.19 What is octet rule?
Q.20 How many electrons M shell can accommodate?