Given below are two statements : Statement I : The metallic radius of Na is \(1.86 \mathrm{~A}^{\circ}\) and the ionic radius of \(\mathrm{Na}^{+}\)is lesser than \(1.86 \mathrm{~A}^{\circ}\). Statement II : Ions are always smaller in size than the corresponding elements. In the light of the above statements, choose the correct answer from the options given below :

(A) Statement I is correct but Statement II is false

(B) Both Statement I and Statement II are true

(C) Both Statement I and Statement II are false

(D) Statement I is incorrect but Statement II is true

JEE Main · 2024 · 05 Apr 2024 · Shift 2 · Classification of Elements and Periodicity

Given below are two statements :

Statement I : The metallic radius of Na is

1.86 A^{\circ}

and the ionic radius of

Na^{+}

is lesser than

1.86 A^{\circ}

.

Statement II : Ions are always smaller in size than the corresponding elements.

In the light of the above statements, choose the correct answer from the options given below :

(A)Statement I is correct but Statement II is false✓ Correct
(B)Both Statement I and Statement II are true
(C)Both Statement I and Statement II are false
(D)Statement I is incorrect but Statement II is true

Answer: (A)

Solution

When Na loses its single valence electron to form

N a^{+}

, the resulting ion has one fewer occupied shell and a higher effective nuclear charge per electron, so its radius is always smaller than the metallic radius of Na — Statement I (

r_{N a^{+}} < 1.86

Å) is correct.
Statement II's blanket claim fails for anions: an anion (e.g.

C l^{-}

) gains electrons, lowering the effective nuclear charge per electron, and is therefore larger than its parent atom. So "ions are always smaller than the corresponding elements" is false.

JEE Main · 2024 · 05 Apr 2024 · Shift 2 · Single correct option

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JEE Main · 2024 · 05 Apr 2024 · Shift 2 · Classification of Elements and Periodicity

Solution

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