JEE Main 2022 — Chemistry Inorganic Chemistry

2022mcqeasy

The metal complex that is diamagnetic is (Atomic number : $\mathrm{Fe},26;\mathrm{Cu},29$ )

Official previous-year question

Held on 26 Jul 2022 · Verified 6 Jul 2026.

Options

A
${K}_{3}[\mathrm{Cu}{(\mathrm{CN})}_{4}]$
B
${K}_{2}[\mathrm{Cu}{(\mathrm{CN})}_{4}]$
C
${K}_{3}[\mathrm{Fe}{(\mathrm{CN})}_{4}]$
D
${K}_{4}[{\mathrm{FeCl}}_{6}]$

Did you get this right?

Solution

${K}_{3}[\mathrm{Cu}{(\mathrm{CN})}_{4}]$ :

${[\mathrm{Cu}{(\mathrm{CN})}_{4}]}^{-3}$

Oxidation number of of copper is ${\mathrm{Cu}}^{+1}$

Electronic configuration of ${\mathrm{Cu}}^{+1}=[\mathrm{Ar}]3{d}^{10}4{s}^{0}$

Due to the absence of unpaired electrons, their spin only magnetic moment is zero, they are diamagnetic in nature

${K}_{2}[\mathrm{Cu}{(\mathrm{CN})}_{4}]$ :

${[\mathrm{Cu}{(\mathrm{CN})}_{4}]}^{2-},({\mathrm{Cu}}^{2+}=[\mathrm{Ar}]3{d}^{9})$ one unpaired electron is present.Hence, paramagnetic in nature.

${K}_{4}[{\mathrm{FeCl}}_{6}]$ :

${[{\mathrm{FeCl}}_{6}]}^{-4}$ , ${\mathrm{Fe}}^{+2}:[\mathrm{Ar}]3{d}^{6}4{s}^{0},\mathrm{one}\mathrm{unpaired}\mathrm{electron}$ .Hence, paramagnetic in nature.

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JEE Main 2022 — Chemistry Inorganic Chemistry

2022mcqeasy

The metal complex that is diamagnetic is (Atomic number : $\mathrm{Fe},26;\mathrm{Cu},29$ )

Official previous-year question

Held on 26 Jul 2022 · Verified 6 Jul 2026.

Options

A
${K}_{3}[\mathrm{Cu}{(\mathrm{CN})}_{4}]$
B
${K}_{2}[\mathrm{Cu}{(\mathrm{CN})}_{4}]$
C
${K}_{3}[\mathrm{Fe}{(\mathrm{CN})}_{4}]$
D
${K}_{4}[{\mathrm{FeCl}}_{6}]$

Did you get this right?

Solution

${K}_{3}[\mathrm{Cu}{(\mathrm{CN})}_{4}]$ :

${[\mathrm{Cu}{(\mathrm{CN})}_{4}]}^{-3}$

Oxidation number of of copper is ${\mathrm{Cu}}^{+1}$

Electronic configuration of ${\mathrm{Cu}}^{+1}=[\mathrm{Ar}]3{d}^{10}4{s}^{0}$

Due to the absence of unpaired electrons, their spin only magnetic moment is zero, they are diamagnetic in nature

${K}_{2}[\mathrm{Cu}{(\mathrm{CN})}_{4}]$ :

${[\mathrm{Cu}{(\mathrm{CN})}_{4}]}^{2-},({\mathrm{Cu}}^{2+}=[\mathrm{Ar}]3{d}^{9})$ one unpaired electron is present.Hence, paramagnetic in nature.

${K}_{4}[{\mathrm{FeCl}}_{6}]$ :

${[{\mathrm{FeCl}}_{6}]}^{-4}$ , ${\mathrm{Fe}}^{+2}:[\mathrm{Ar}]3{d}^{6}4{s}^{0},\mathrm{one}\mathrm{unpaired}\mathrm{electron}$ .Hence, paramagnetic in nature.

JEE Main 2022 — Chemistry Inorganic Chemistry

Options

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Solution

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JEE Main Inorganic Chemistry in other years

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JEE Main 2022 — Chemistry Inorganic Chemistry

Options

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Solution

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JEE Main Inorganic Chemistry in other years

More JEE Main Inorganic Chemistry questions

Other Chemistry topics for JEE Main

Physical Chemistry

Organic Chemistry

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