The first excitation potential of a given atom is `10.2V`,then the ionisation potential is

Options

A. 20.4 V
B. 13.6 V
C. 30.6 V
D. 40.8 V

Answer

B

Explanation

Ionisation potential is the energy required to remove electron from lowest orbit.
`:. E_(n)=(me^(4))/(8 in_(0)^(2)n^(2)h^(2))`
`:. E_(1)=(9.1xx10^(-31)xx(1.6xx10^(-19))^(4))/(8xx(8.85xx10^(-12))^(2)xx1xx(6.63xx10^(-34))^(2))` Joule
`=+13.6` eV