Question

define bohrs model of an atom

Answer 1

According to Neil Bohr, positively charged proton is present in the nucleus and negatively charged electron are moving in their respective orbits called energy shells.

Answer 2

Bohr’s Model of Atom:

Neils Bohr, a Danish physicist, in 1913 proposed model of atom which rectified the problems left by Rutherford’s Model. He proposed that

• Electrons revolve round the nucleus in a fixed orbit.

• He called these orbits as ‘stationary orbit’.

• Each stationary orbit is associated with fixed amount of energy, thus electrons do not radiate energy as long as they keep on revolving around the nucleus in fixed orbit.

The circular path around the nucleus is called orbit, energy level or shell. Energy level are represented by letter – K, L, M, N, …. and so on.

Therefore,

• 1st orbit is denoted by – K

• 2nd orbit is denoted by – L

• 3rd orbit is denoted by – M, and so on.

The orbits are denoted by 1, 2, 3, …. and so on.

Distribution of Electrons in a Orbit or Shell:

The distribution of electrons in an orbit can be obtained by using formula

2n^2

where ‘n’ is number of orbit.