explain bohr model of an atom !?

Neils Bohr gave atomic model in 1913.The main points of this model are:

1) An atom consists of a central positive part called the nucleus which contains all the protons and neutrons.

2) Electrons which are present outside the nucleus revolve around the nucleus in definite circular paths called orbits or shells.

3) Each orbit has a fixed energy and the orbitals are represented by the symbols K, L,M, N etc or by the numbers 1,2,3 …

4) Each orbit can accommodate not more than a fixed number of electrons.

5) Electrons moving in the same orbit donot lose or gain energy.

6) Electrons lose energy on jumping from a higher orbit to lower one and vice-versa.

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The Bohr's Model of Atom can be described as follows :

An atom is made up of three particles : electrons, protons and neutrons. Electrons have negative charge, protons have positive charge whereas neutrons have no charge, they are neutral. Dueto the presence of equal number of negative electrons and positive protons, the atom on the whole is electrically neutral.
The protons and neutrons are locatted in a small nucleus at the centre of the atom. Due to the presence of protons, nucleus is positively charged.
The electrons revolve rapidly round the nucleus in fixed circular paths called energy levels or shells. The energy levels ar shells are represented in two ways : either by the number 1, 2, 3 , 4, 5 and 6 or by the letters K, L, M, N, O and P. The energy levels are counted from the centre outwards.
There is a limit to the number of electrons which each energy level (or shell) can hold. For example, the first energy level (or K shell) can hold a maximium of 2 electrons; second energy level (or L shell) can hold a maximium of 8 electrons; third energy level ( or M shell) can hold a maximium of 18 electrons and the fourth energy level ( or N shell) can hold a maximium of 32 electrons.
Each energy level ( or shell) is associated with a fixed amount of energy, the shell nearest to the nucleus having minimum energy and the shell farthest from the nucleus having the maximium energy.
There is no change in the energy of electrons as long as they keep revolving in the same energy level, and the atom remains stable. The change in the energy of an electron takes place only when it jumps from a lower energy level to a higher energy level or when it comes down from a higher energy level to a lower energy level. when an electrons gains an energy, it jumps from a lower energy to a higher energy level, and when an electron comes down from a higher energy level to a lower energy level, it loses energy.

The Bohr 's Model of Atom can be described as follows :

An atom is made up of three particles : electrons, protons and neutrons. Electrons have negative charge, protons have positive charge whereas neutrons have no charge, they are neutral. Dueto the presence of equal number of negative electrons and positive protons, the atom on the whole is electrically neutral.
The protons and neutrons are locatted in a small nucleus at the centre of the atom. Due to the presence of protons, nucleus is positively charged.
The electrons revolve rapidly round the nucleus in fixed circular paths called energy levels or shells. The energy levels ar shells are represented in two ways : either by the number 1, 2, 3 , 4, 5 and 6 or by the letters K, L, M, N, O and P. The energy levels are counted from the centre outwards.
There is a limit to the number of electrons which each energy level (or shell) can hold. For example, the first energy level (or K shell) can hold a maximium of 2 electrons; second energy level (or L shell) can hold a maximium of 8 electrons; third energy level ( or M shell) can hold a maximium of 18 electrons and the fourth energy level ( or N shell) can hold a maximium of 32 electrons.
Each energy level ( or shell) is associated with a fixed amount of energy, the shell nearest to the nucleus having minimum energy and the shell farthest from the nucleus having the maximium energy.
There is no change in the energy of electrons as long as they keep revolving in the same energy level, and the atom remains stable. The change in the energy of an electron takes place only when it jumps from a lower energy level to a higher energy level or when it comes down from a higher energy level to a lower energy level. when an electrons gains an energy, it jumps from a lower energy to a higher energy level, and when an electron comes down from a higher energy level to a lower energy level, it loses energy.

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