Assertion : Potassium and caesium are useful as electrodes in photoelectric cells.
Reason : Potassium and caesium, when irradiated with light, the light energy absorbed is sufficient to eject out the electron from a atom.

Options

A. If both (A) and (R) are correct and (R) is the correct explanation of (A).
B. If both (A) and (R) are correct, but (R) is not the correct explanation of (A).
C. If (A) is correct, but (R) is incorrect.
D. If both (A) and (R) are incorrect.

Answer

A

Explanation

Low ionisation energies of potassium and caesium.