NEET UG 2015 — Chemistry Physical Chemistry

2015mcqmedium

The number of $d$ -electrons in ${\mathrm{Fe}}^{2+}(Z=26)$ is not equal to the number of electrons in which one of the following?

Official previous-year question

Held on 30 Apr 2015 · Verified 9 Jul 2026.

Options

A
$s$ -electrons in $\mathrm{Mg}(Z=12)$
B
$p$ -electrons in $\mathrm{Cl}(Z=17)$
C
$d$ -electrons in $\mathrm{Fe}(Z=26)$
D
$p$ -electrons in $\mathrm{Ne}(Z=10)$

Did you get this right?

Solution

${}_{26}{\mathrm{Fe}}^{2+}{\Rightarrow }_{18}[\mathrm{Ar}] 3{d}^{6} ;6d$ -electrons

${}_{17}\mathrm{Cl}\Rightarrow 1{s}^{2} 2{s}^{2} 2{p}^{6} 3{s}^{2} 3{p}^{5} ;11p$ -electrons

$\mathrm{Mg}=1{s}^{2}2{s}^{2}2{p}^{6}3{s}^{2};6s$ -electrons

$d$ -electrons in $\mathrm{Fe}={ }_{18}\mathrm{Ar}3{d}^{6}=6$

$p$ -electrons in $\mathrm{Ne}=1{s}^{2}2{s}^{2}2{p}^{6}=6$

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NEET UG 2015 — Chemistry Physical Chemistry

2015mcqmedium

The number of $d$ -electrons in ${\mathrm{Fe}}^{2+}(Z=26)$ is not equal to the number of electrons in which one of the following?

Official previous-year question

Held on 30 Apr 2015 · Verified 9 Jul 2026.

Options

A
$s$ -electrons in $\mathrm{Mg}(Z=12)$
B
$p$ -electrons in $\mathrm{Cl}(Z=17)$
C
$d$ -electrons in $\mathrm{Fe}(Z=26)$
D
$p$ -electrons in $\mathrm{Ne}(Z=10)$

Did you get this right?

Solution

${}_{26}{\mathrm{Fe}}^{2+}{\Rightarrow }_{18}[\mathrm{Ar}] 3{d}^{6} ;6d$ -electrons

${}_{17}\mathrm{Cl}\Rightarrow 1{s}^{2} 2{s}^{2} 2{p}^{6} 3{s}^{2} 3{p}^{5} ;11p$ -electrons

$\mathrm{Mg}=1{s}^{2}2{s}^{2}2{p}^{6}3{s}^{2};6s$ -electrons

$d$ -electrons in $\mathrm{Fe}={ }_{18}\mathrm{Ar}3{d}^{6}=6$

$p$ -electrons in $\mathrm{Ne}=1{s}^{2}2{s}^{2}2{p}^{6}=6$

Your note

NEET UG Physical Chemistry in other years

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NEET UG 2015 — Chemistry Physical Chemistry

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Solution

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NEET UG 2015 — Chemistry Physical Chemistry

Options

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Solution

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NEET UG Physical Chemistry in other years

More NEET UG Physical Chemistry questions

Other Chemistry topics for NEET UG

Organic Chemistry

Inorganic Chemistry

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