When electromagnetic radiation of wavelength 300 nm falls on the surface of a metal, electrons are emitted with the kinetic energy of 1.68 × 10^5 J…

When electromagnetic radiation of wavelength $\displaystyle 300$ nm falls on the surface of a metal, electrons are emitted with the kinetic energy of $\displaystyle 1.68 \times 10^5 \mathrm{~J} \mathrm{~mol}^{-1}$. What is the minimum energy needed to remove an electron from the metal? $\displaystyle \left(\mathrm{h}=6.626 \times 10^{-34} \mathrm{Js}, \mathrm{c}=3 \times 10^8 \mathrm{~ms}^{-1}, \mathrm{~N}_{\mathrm{A}}=6.022 \times 10^{23} \mathrm{~mol}^{-1}\right)$