Question

The maximum Coulomb force that can act on the electron due to the nucleus in a hydrogen atom will be:-

• A. $0.82\times {10}^{-8}N$
• B. $0.082\times {10}^{-8}N$
• C. $8.2\times {10}^{-8}N$
• D. $820\times {10}^{-8}N$

Answer 1

The correct option is C $8.2\times {10}^{-8}N$

Acccording to Bohr's Theory,

$R_n=\left(0.53A\right)\frac{n^2}{2}$

where, Radius of $n^{th}$ shell of an atom with atomic no. $z$

Here, to get maximun coulumbic force, radius should be minimum.

So $n=1,z=1$ for Hydrogen $R_1=0.53R$

$Coulumbicforce=\frac{K{e}^2}{R_1^2}=\frac{9\times {10}^9\times {(1.6\times {10}^{-19})}^2}{(0.53\times {10}^{-10})}$

Fc= $8.202\times {10}^{-8}N$

option-$C$ is correct