The ionization enthalpy of hydrogen atom is `1.312 xx 10^6 J mol^-1`. The energy required to excite the electron in the atom from `n= 1` to `n = 2` is :

Options

A. ` 8. 51 xx 10^5 J mol^(-1)`
B. `6.56 xx 10^5 J mol^(-1)`
C. ` 7. 56 xx 10^5 J mol^(-1)`
D. ` 9. 84 xx 10^5 J mol^(-1)`

Answer

D

Explanation

` Delta = E_2 -E_1 =- E_1 /2^2 + E_11^1`
` =- ( 1.312 xx 10^6) 2^2 + 1.312 xx 10^6`
` = 9. 84 xx10^5 J mol^(-1)`.