Bohr’s Atomic Model

Bohr’s Atomic model is a model about Atomic structure. Niels Henrik David Bohr established a theory and give by Bohr. Bohr put forward two impotant postulates for the atomic structure.

Postulate number 1.

Electron in an atom always revolve around the nucleus in a fixed stationary Orbit.These are called permitted Orbit or permissible Orbit.Angular momentum of electron revolving around the nucleus in Orbit is equal to the integral multiple of h/2π.

i.e Angular momentum = n. h/2π

or, radius * linear momentum = nh/2π

or, r.p = nh/2π

or, r.m.v = nh/2π

or, mvr = nh/2π …………1)

where m = mass of electrons

v = orbital velocity of electron

Postulate number 2.

Electron moving in a permitted orbit doesnot emit any radiation when electron jumps from higher orbit to lower orbit. It emits radiation of fixed energy and this fixed energy is equal to difference in energy between transitional of orbits. Electron

i.e ΔE = E2 – E1

or, hf = E2 -E1

or, E2 – E1 = hc/lamda ……2)

where E2 = Energy of electrons higher orbit

E1 = Energy of orbits electron in lower orbit

h = planck’s Constant

Lamda = wavelength of radiation

C = velocity of light

Equation 1) and 2) is the required expression of Bohr’s postulates for the atomic structure.

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