19. State the postulates of Bohr's atomic model. Write the relation for the energy of
an electron in a given orbit in terms of its mass and the charge. In what way it
was better than Rutherford's model?
Answers
Answer:
● In an atom, electrons (negatively charged) revolve around the positively charged nucleus in a definite circular path called as orbits or shells.
● Each orbit or shell has a fixed energy and these circular orbits are known as orbital shells.
● The energy levels are represented by an integer (n=1, 2, 3…) known as the quantum number. This range of quantum number starts from nucleus side with n=1 having the lowest energy level. The orbits n=1, 2, 3, 4… are assigned as K, L, M, N…. shells and when an electron attains the lowest energy level it is said to be in the ground state.
● The electrons in an atom move from a lower energy level to a higher energy level by gaining the required energy and an electron moves from a higher energy level to lower energy level by losing energy.
The relation is -E0/n2 where E0=13.6eV and n =1,2,3,...
