Question

Plz answer it with explanation.... What will happen to Cu, Ag, Fe, Pt, W​

Answer 1

Answer: According to my knowledge, Li, Na, K, Mg are the four metals which should show the photoelectric effect in this case according to the data you have provided. Now lets attempt an explanation.

Explanation: We have E= hc/λ

Now putting the values, we have,

E= [6.626*10^(-34)*3*10^8]/3*10^(-7)   {since 300 nm= 3*10^(-7)m}

 = [1.987*10^(-25)]/3*10^(-7)

 = 6.626*10^(-19).

converting to electron volts we have,

E (eV)= 6.626*10^(-19)/1.6*10^(-19)

         = 4.2 approx.

So, Li, Na, K, Mg can show photoelectric effect here.