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For the ground state, the electron in th...

For the ground state, the electron in the Hatom has an angular momentum = `(nh)/(2pi)`according to the simple Bohr model. Angular momentum is a vector and hence there will be infinitely many orbits with the vector pointing in all possible directions. In actuality, this is not true,

A

because Bohr model gives incorrect values of angular momentum.

B

because only one of these would have a minimum energy.

C

angular momentum must be in the direction of spin of electron

D

because electrons go around only in horizontal orbits.

Text Solution

Verified by Experts

The correct Answer is:
A
Because electron in an atom performs two types of motion in its orbit as under.
(i) Orbital motion about an axis passing through nucleus.
(ii) Spinning motion about its own axis.
Due to above two types of motion, electron possesses certain definite values of angular momentum. (i.e. these values are quantized).
Here if we consider spinning motion, total angular momentum values for an electron are not equal to `(nh)/(2pi)` (where n, 1, 2, 3, ..., and h = Planck.s constant). It means that these values are not according to Bohr model
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