Medium MCQ +4 / -1 PYQ · JEE Mains 2021

Match List - I with List - II.

List I
Electronic configuration
List II
${\Delta _i}H$ in kJ $mo{l^{ - 1}}$
(a) $1{s^2}2{s^2}$ (i) 801
(b) $1{s^2}2{s^2}2{p^4}$ (ii) 899
(c) $1{s^2}2{s^2}2{p^3}$ (iii) 1314
(d) $1{s^2}2{s^2}2{p^1}$ (iv) 1402

Choose the most appropriate answer from the options given below :

  1. A (a) $\to$ (i), (b) $\to$ (iii), (c) $\to$ (iv), (d) $\to$ (iii)
  2. B (a) $\to$ (iv), (b) $\to$ (i), (c) $\to$ (ii), (d) $\to$ (iii)
  3. C (a) $\to$ (ii), (b) $\to$ (iii), (c) $\to$ (iv), (d) $\to$ (i) Correct answer
  4. D (a) $\to$ (i), (b) $\to$ (iv), (c) $\to$ (iii), (d) $\to$ (ii)

Solution

(a) 1s<sup>2</sup> 2s<sup>2</sup> $\to$ Be<br><br> (b) 1s<sup>2</sup> 2s<sup>2</sup> 2p<sup>4</sup> $\to$ O<br><br> (c) 1s<sup>2</sup> 2s<sup>2</sup> 2p3 $\to$ N<br><br> (d) 1s<sup>2</sup> 2s<sup>2</sup> 2p<sup>1</sup> $\to$ B<br><br> The ionization enthalpy order is<br><br> B &lt; Be &lt; O &lt; N<br><br> Be has more IE compared to B due to extra stability &amp; N has more IE compared to oxygen due to extra stability.<br><br> Hence, N $\to$ 1402 kJ/mol<br><br> O $\to$ 1314 kJ/mol<br><br> B $\to$ 801 kJ/mol<br><br> Be $\to$ 899 kJ/mol

About this question

Subject: Chemistry · Chapter: Periodic Table and Periodicity · Topic: Periodic Trends

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