JEE Main 2019 — Chemistry Inorganic Chemistry

2019mcqmedium

Two complexes $[\mathrm{Cr}{({H}_{2}O)}_{6 }]{\mathrm{Cl}}_{3} (A)$ and $[\mathrm{Cr}{({\mathrm{NH}}_{3})}_{6}]{\mathrm{Cl}}_{3}(B)$ are violet and yellow coloured, respectively, The incorrect statement regarding them is:

Official previous-year question

Held on 9 Jan 2019 · Verified 6 Jul 2026.

Options

A
Both are paramagnetic with three unpaired electrons
B
${\Delta }_{0}$ value of $(A)$ is less than that of $(B)$
C
${\Delta }_{0}$ values of $(A)$ and $(B)$ are calculated from the energies violet and yellow light, respectively.
D
Both absorb energies corresponding to their complementary colors.

Did you get this right?

Solution

${({\Delta }_{0})}_{A}<{({\Delta }_{0})}_{B}$ , both complex have $CN=6,$ B has strong field ligand and A has weak field ligand

so ${({\Delta }_{0})}_{A}< {({\Delta }_{0})}_{B}$

In both complexes, $Cr$ has $3$ unpaired electrons and hence, will be paramagnetic $[Cr({H}_{2}O)]C{l}_{3}$

$[{\mathrm{Cr}}^{+3}=1{s}^{2} 2{s}^{2} 2{p}^{6} 3{s}^{2} 3{p}^{6} 3{d}^{3}]$ in strong field ligand or weak field ligand is ${t}_{2g}^{1,1,1},e{g}^{o}$

JEE Main 2019 Chemistry, Coordination Compounds — solution figure

${\Delta }_{0}$ order will be compared by spectrochemical series not by energies of violet and yellow light. Hence incorrect

Your note

JEE Main Inorganic Chemistry in other years

Inorganic Chemistry 2026 Inorganic Chemistry 2025 Inorganic Chemistry 2024 Inorganic Chemistry 2023 Inorganic Chemistry 2022 Inorganic Chemistry 2021 Inorganic Chemistry 2020 Inorganic Chemistry 2018 Inorganic Chemistry 2017 Inorganic Chemistry 2016 Inorganic Chemistry 2015 Inorganic Chemistry 2014

Keep practicing Inorganic Chemistry

Work through every JEE Main Inorganic Chemistry PYQ, year by year.

Browse all Chemistry topics

Options

Both are paramagnetic with three unpaired electrons

${\Delta }_{0}$ value of $(A)$ is less than that of $(B)$

${\Delta }_{0}$ values of $(A)$ and $(B)$ are calculated from the energies violet and yellow light, respectively.

Both absorb energies corresponding to their complementary colors.

Solution

${({\Delta }_{0})}_{A}<{({\Delta }_{0})}_{B}$ , both complex have $CN=6,$ B has strong field ligand and A has weak field ligand

so ${({\Delta }_{0})}_{A}< {({\Delta }_{0})}_{B}$

In both complexes, $Cr$ has $3$ unpaired electrons and hence, will be paramagnetic $[Cr({H}_{2}O)]C{l}_{3}$

$[{\mathrm{Cr}}^{+3}=1{s}^{2} 2{s}^{2} 2{p}^{6} 3{s}^{2} 3{p}^{6} 3{d}^{3}]$ in strong field ligand or weak field ligand is ${t}_{2g}^{1,1,1},e{g}^{o}$

JEE Main 2019 Chemistry, Coordination Compounds — solution figure

${\Delta }_{0}$ order will be compared by spectrochemical series not by energies of violet and yellow light. Hence incorrect

JEE Main 2019 — Chemistry Inorganic Chemistry

Options

Did you get this right?

Solution

Your note

JEE Main Inorganic Chemistry in other years

More JEE Main Inorganic Chemistry questions

Other Chemistry topics for JEE Main

Physical Chemistry

Organic Chemistry

Keep practicing Inorganic Chemistry

JEE Main 2019 — Chemistry Inorganic Chemistry

Options

Did you get this right?

Solution

Your note

JEE Main Inorganic Chemistry in other years

More JEE Main Inorganic Chemistry questions

Other Chemistry topics for JEE Main

Physical Chemistry

Organic Chemistry

Keep practicing Inorganic Chemistry