The reduction potential of hydrogen electrode in neutral solution at 298K is

At 298K the concentration of H⁺ in neutral solution is 10^-7 mole/Litre.
$\left[H^{+}\right]={10}^{-7}mole/Litre$
${\mathrm{P}}^{\mathrm{H}}=7$
For Hydrogen electrode  $E_{RP}=-0.059\times P^H=-0.059\times 7=-0.413volts$