The ionization enthalpy of hydrogen atom is $1.312\times 10^6\;Jmol^{-1}$.The energy required to excite the electron in the atom from $n=1$ to $n=2$ is

Question

$\begin{array}{1 1}(a)\;8.51\times 10^5Jmol^{-1}\\(b)\;6.56\times 10^5Jmol^{-1}\\(c)\;7.56\times 10^5Jmol^{-1}\\(d)\;9.84\times 10^5Jmol^{-1}\end{array}$