1.

The first ionisation potential of Na, Mg, Al and Si are in the order(a) Na <Mg>AI< Si(b) Na > Mg > AI>Si(c) Na< Mg<AI>Si(d) Na > Mg > Al<Si

Answer»

Correct option (a) Na <Mg>AI< Si

Explanation:

First ionisation potential increases from left to right across a period but Mg has extra stability than Al, due to full-filled 3s -orbitals.

Na11  = 1s2,2s2,2p6,3s1

Mg12  = 1s2,2s2,2p6,3s2

AI13  =  1s2,2s2,2p6,3s2, 3p1

Si14  = 1s2,2s2,2p6,3s2, 3p2

Thus, correct order of first ionisation potential is :

Na<Mg>AL<Si



Discussion

No Comment Found

Related InterviewSolutions