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Question
The simple Bohr model is not applicable to He 4 atom because ______.
- He4 is an inert gas.
- He4 has neutrons in the nucleus.
- He4 has one more electron.
- electrons are not subject to central forces.
Options
a and c
a, c and d
b and d
c and d
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Solution
c and d
Explanation:
Bohr proposed a model for the hydrogen atoms which is also applicable for some lighter atoms in which a single electron revolves around a stationary nucleus of positive charge Ze (called hydrogen-like atom). It is valid only for one-electron atoms, e.g. : H, He+, Li+2, Na+1 etc.
The Bohr model is not applicable to He4, as it has one more electron and electrons are not subject to central forces.
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