Why is it difficult to remove a free electron from copper than sodium? Which has higher threshold wavelength?

Asked by Topperlearning User | 4th Jun, 2014, 01:23: PM

Expert Answer:

The work function of copper is 4.5 eV while that for sodium is 2 eV. Therefore, radiation of more energy is required to remove a free electron from copper as compared to sodium. Since threshold radiation is inversely proportional to the work function, its value will be more for sodium.

 

Answered by  | 4th Jun, 2014, 03:23: PM