Question

12. Photoelectrons are removed with kinetic energy 1.864 x 10-21 J, when photons of light with
energy 4.23 * 10-19 J fall on the metal. What is the minimum energy required per mole to
remove an electron from potassium metal?​

Answer 1

Answer:

Minimum energy required = 4.23×10−19J−1.86×10−21J

                                             = 4.2114×10−19J

This is the minimum energy required to remove the electron. 

We then convert into units of energy per mole. 

Minimum energy required per mole =4.2114×10−19J×6.022×1023mol−1

                                                              =253.608 KJ/mol