Question

Which of the following are more likely to form cations ? Also specify the charge on these cations.
Na, Cl, Ca, Al, S, Mg, He

Answer 1

Na

it will prefer to donate an electron and gain a positive charge

Na+

Cl

Valency-1(7e-in outermost orbit)

it requires only one electron to complete it's octet hence it will gain 1 electron

Cl-

Ca2+

valency-2

it has 2 ELECTRONS in it's outermost orbit HENCE it will loose 2 electrons in order to become stable

Al 3+

valency-3

it has 3ELECTRONS in it's outermost orbit HENCE it will loose 3 electrons in order to become stable

S

+6 or +2(due to presence of d ORBITALS it can expand it's octet)

Mg 2+

valency-2

it has 2 ELECTRONS in it's outermost orbit HENCE it will loose 2 electrons in order to become stable

He

+2(valency-2

it has 2 ELECTRONS in it's outermost orbit HENCE it will loose 2 electrons in order to become stable)

I hope this helps ( ╹▽╹ )