Question

Explain Bhor's model

Answer 1

According to bohr's model:-

1. The atom contains a small nucleus at its centre.

2. The whole mass of the atom is concentrated at the nucleus and the volume of nucleus is lesser than the volume of the atom by a ration of 1:10^5.

3. All the protons as well as neutrons of the atom are contained in the nucleus.

4. The electrons of the atom revolve round the nucleus in difinite circular paths called orbits or shells which are disignated as K, L, M N etc. or numbered as (n) = 1, 2, 3, 4 etc. outward from the nucleus.

5.Each orbit is associated with a fixed amount of energy. Hence. these orbits are also called energy levels or energy shells.

6. The energy of the atom changes when an electron jumps from one state to another state. As long as an electron remains in a specific orbit, it doesn't lose or gain energy.

Answer 2

a) Electrons revolve round the nucleus in a fixed orbit known as " discrete orbits of electrons "

b) While revolving around the orbits , the electrons would not radiate energy

c) The maximum number of electrons that can be accommodated in a shell is given by the formula 2n² , where n is the energy level or orbit number.
1st orbit is denoted by K
2nd orbit is denoted by L
3rd orbit is denoted by M, and so on.


K shell = 2 × 1² = 2 electrons

L shell = 2 × 2² = 8 electrons

and so on ........



d) The outer shells cannot be filled unless inner shells are filled.

e)The outermost shell of an atom cannot accommodate more than 8 electrons, even if it has a capacity to accommodate more electrons.