If the binding energy of electrons in a metal is 250 kJ `"mol"^(-1)` , what is the threshold frequency of the striking photons ?

Explanation

Binding energy of 1 mole electrons = 250 kJ
Binding energy of 1 electron `=(250 kJxx(1"electron"))/((6.022xx10^(23)"electrons"))=4.15xx10^(-22)kJ=4.15xx10^(-19)J`
Binding energy (E)`=hv^(0)`
`:.` Threshold frequency `(v^(0))=(E)/(h)=((4.15xx10^(-19)J))/((6.626xx10^(-34)Js))=6.26xx10^(14)s^(-1)`.