Question

All of the following are isoelectronic with Ca2+ except

A. P3-.

B. Mg1+.

C. K1+.

D. S2–.

E. Cl1–.

Answer 1

Help!

Answer 2

do you know what is meant by isoelectronic

Answer 3

isoelectronic = same number of e;ectrons in outer shell

using periodic tables, we see Ca2+ forms Ar octet.
so, which of the options does nor form the same octet?

Answer 4

adding electrons = move right in the Periodic table
removing electrins = move left

Answer 5

Mg1+?

Answer 6

bingo

Answer 7

Thanks :)