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Class 11
Chemistry
Structure of Atom
which of the following are isoelectronic species i...

Question:
Which of the following are isoelectronic species i.e., those having the same number of electrons?

Na⁺, K⁺, Mg²⁺, Ca²⁺, S^2–, Ar

Answer:

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 S^2- = 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⁺, S^2– and Ar (18 electrons each)

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Question:
Which of the following are isoelectronic species i.e., those having the same number of electrons?

Na⁺, K⁺, Mg²⁺, Ca²⁺, S^2–, Ar

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Question: Which of the following are isoelectronic species i.e., those having the same number of electrons? Na+, K+, Mg2+, Ca2+, S2–, Ar

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Question:
Which of the following are isoelectronic species i.e., those having the same number of electrons?

Na⁺, K⁺, Mg²⁺, Ca²⁺, S^2–, Ar