Arrange the following in increasing order of ionisation energy: Na, Mg, Al, Si, P, S, Cl, Ar — JEE Chemistry
Arrange the following in increasing order of ionisation energy: Na, Mg, Al, Si, P, S, Cl, Ar
1 Answer
PPrakashGurung52
✓ Accepted
· 2mo ago
▲ 3
General trend: ionisation energy increases across a period. However, exceptions occur:
- $IE(Mg) > IE(Al)$: Al loses a 3p electron (easier) vs Mg losing a 3s electron
- $IE(P) > IE(S)$: P has half-filled 3p (extra stable); S loses one electron from a paired orbital (easier)
$$Na < Al < Mg < Si < S < P < Cl < Ar$$
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Discussion (3)
T
Is there a faster shortcut for this in the actual exam? Time is tight.
N
Clean and to the point. Bookmarking this for revision.
VA
Good follow-up questions — remember to always state your assumptions in the JEE subjective section.