Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A) : The ionic radii of $O^{2–}$ and $Mg^{2+}$ are same. Reason (R) : Both $O^{2–}$ and $Mg^{2+}$ are isoelectronic species. In the light of the above statements, choose the correct answer from the options given below.

Question

Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A) : The ionic radii of  $O^{2–}$  and  $Mg^{2+}$  are same. Reason (R) : Both  $O^{2–}$  and  $Mg^{2+}$  are isoelectronic species. In the light of the above statements, choose the correct answer from the options given below.

cdquestions Admin · Accepted Answer

Correct order of ionic radii: $O^{–2} > Mg^{+2}$ This is because among isoelectronic species, the size of anions are greater than the size of cations. Statement (II) is correct as both  $O^{–2}$  and  $Mg^{+2}$  are isoelectronic. Hence, the correct option is (D): (A) is false but (R) is true.

Answer

Both (A) and (R) are true and (R) is the correct explanation of (A).

Answer

Both (A) and (R) are true but (R) is not the correct explanation of (A).

Answer

(A) is true but (R) is false.

Answer

(A) is false but (R) is true.

The Correct Option is D

Solution and Explanation

Top Questions on Atomic Models

Questions Asked in JEE Main exam

Concepts Used:

Atomic Models

There are five atomic models:

John Dalton’s atomic model - Dalton´s Billiard Ball (Solid Sphere) Model

J.J. Thomson’s model - Plum Pudding model

Ernest Rutherford’s model - Nuclear model

Niels Bohr’s model - Planetary model

Erwin Schrödinger’s model - Electron Cloud Model/Quantum Model