The radius of hydrogen atom in its ground state is `5.3 xx 10^(-11)m`. After collision with an electron, it is found to have a radius of `21.2 xx 10^(-11)m`. What is the principal quantum number of the final state of the atom?

Options

A. n=4
B. n=2
C. n=16
D. n=3

Answer

B

Explanation

`r_(n)= r_(0) n^(2)`
`rArr n^(2)= (21.2 xx 10^(-11))/(5.3 xx 10^(-11)) = 4 rArr n= 2`