I_1of an element X is 899 kJ "mole"^(-1) and that of another element Y is 801kJ mole-1. Then X and Y may be

I_1of an element X is 899 kJ "mole"^(-1) and that of another element Y

1.	I_1of an element X is 899 kJ "mole"^(-1) and that of another element Y is 801kJ mole-1. Then X and Y may be
Answer» LI,Be Be,B B,C C,N Answer :B