JEE Main 2020 — Coordination Compounds Question with Solution
From: JEE Main 2020 (Online) 9th January Morning Slot
Question
Complex X of composition Cr(H2O)6Cln
has a spin only magnetic moment of 3.83
BM. It reacts with AgNO3 and shows
geometrical isomerism. The IUPAC
nomenclature of X is :
Choose an option
Show full solutionCorrect option: C
Correct answer
CTetraaquadichlorido chromium (III)
chloride dihydrate
Step-by-step explanation
Given complex Cr(H2O)6Cln
As the magnetic mement is 3.83 BM then
Spin only magnetic moment = BM = 3.83
n = 3
Chromium in +3 oxidation state so molecular formula is Cr(H2O)6Cln.
This formula have following isomers
(a) [Cr(H2O)6]Cl3 : react with AgNO3 but does not show geometrical isomerism.
(b) [Cr(H2O)5Cl]Cl2.H2O react with AgNO3 but does not show geometrical isomerism.
(c) [Cr(H2O)4Cl2]Cl.2H2O react with AgNO3 & show geometrical isomerism.
(d) [Cr(H2O)3Cl3].3H2O does not react with AgNO3 & show geometrical isomerism.
Compound will be [Cr(H2O)4Cl2] Cl.2H2O
IUPAC NAME : Tetraaquadichlorido chromium(III) chloride dihydrate
As the magnetic mement is 3.83 BM then
Spin only magnetic moment = BM = 3.83
n = 3
Chromium in +3 oxidation state so molecular formula is Cr(H2O)6Cln.
This formula have following isomers
(a) [Cr(H2O)6]Cl3 : react with AgNO3 but does not show geometrical isomerism.
(b) [Cr(H2O)5Cl]Cl2.H2O react with AgNO3 but does not show geometrical isomerism.
(c) [Cr(H2O)4Cl2]Cl.2H2O react with AgNO3 & show geometrical isomerism.
(d) [Cr(H2O)3Cl3].3H2O does not react with AgNO3 & show geometrical isomerism.
Compound will be [Cr(H2O)4Cl2] Cl.2H2O
IUPAC NAME : Tetraaquadichlorido chromium(III) chloride dihydrate
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