Question

which of the following are isoelectronic species Na+ ,K+, Mg2+,Ca2+,S2-, Ar​

Answer 1

Answer:

na+ ca2+, s2- are the isoelectronic species

Answer 2

Answer:

1) Na+ and Mg2+ (10 electrons each)

2) K+, Ca2+, S2– and Ar (18 electrons each)

Explanation:

Isoelectronic species = they are the species belonging to different atoms or ions which have same number of electrons but different magnitude of nuclear charge.

Now, A positive charge denotes the loss of an electron & A negative charge denotes the gain of an electron by a species.

 

1) Number of electrons in sodium (Na) = 11

Therefore, Number of electrons in (Na+) = 10

2) Number of electrons in K+ = 18

3) Number of electrons in Mg2+ = 10

4) Number of electrons in Ca2+ = 18

5) Number of electrons in sulphur (S) = 16

∴ Number of electrons in S2- = 18

6) Number of electrons in argon (Ar) = 18

 

Hence, the following are isoelectronic species:

1) Na+ and Mg2+ (10 electrons each)

2) K+, Ca2+, S2– and Ar (18 electrons each)