Which one of the following complexes will exhibit the least paramagnetic behaviour ?

STUDY MATERIALS
COURSES
MORE
SUCCESS STORY
ADMISSION
STORE

Back

JEE ADVANCE

CLASS XI - XII
CRASH COURSE

CLASS XI - XII

CRASH COURSE

JEE MAIN

CLASS XI - XII
CRASH COURSE

CLASS XI - XII

CRASH COURSE

NEET

CLASS XI - XII
CRASH COURSE

CLASS XI - XII

CRASH COURSE

BITSAT

CLASS XI - XII

CLASS XI - XII

CBSE BOARD

CLASS IX

CLASS X

CLASS XI

CLASS XII

CLASS VI

CLASS VII

CLASS VIII

UP BOARD

CLASS IX
CLASS X
CLASS XI
CLASS XII

CLASS IX

CLASS X

CLASS XI

CLASS XII

CUET

CRASH COURSE

CRASH COURSE

Courses

CLASSROOM COURSES
ONLINE COURSES

ONLINE COURSES

Q.
Which one of the following complexes will exhibit the least paramagnetic behaviour

[Atomic number, Cr = 24, Mn = 25, Fe = 26, Co = 27] [2024]

1 ${[Co {(H_{2} O)}_{6}]}^{2 +}$

2 ${[Mn {(H_{2} O)}_{6}]}^{2 +}$

3 ${[Fe {(H_{2} O)}_{6}]}^{2 +}$

4 ${[Cr {(H_{2} O)}_{6}]}^{2 +}$

Ans.
(1)

Complex Electronic configuration
of central metal ion
without splitting Electronic configuration
after splitting Number of unpaired
electrons

${[{Co(H}_{2} {O)}_{6}]}^{2 +}$ ${Co}^{2 +} = {}_{18}{[Ar]} 3 d^{7}$ $t_{2 g}^{2, 2, 1} e_{g}^{1, 1}$ 3

${[{Mn(H}_{2} {O)}_{6}]}^{2 +}$ ${Mn}^{2 +} = {}_{18}{[Ar]} 3 d^{5}$ $t_{2 g}^{1, 1, 1} e_{g}^{1, 1}$ 5

${[{Fe(H}_{2} {O)}_{6}]}^{2 +}$ ${Fe}^{2 +} = {}_{18}{[Ar]} 3 d^{6}$ $t_{2 g}^{2, 1, 1} e_{g}^{1, 1}$ 4

${[{Cr(H}_{2} {O)}_{6}]}^{2 +}$ ${Cr}^{2 +} = {}_{18}{[Ar]} 3 d^{4}$ $t_{2 g}^{1, 1, 1} e_{g}^{1, 0}$ 4

Paramagnetic nature $\propto$ number of unpaired electrons.

Solution

Q.
Which one of the following complexes will exhibit the least paramagnetic behaviour

[Atomic number, Cr = 24, Mn = 25, Fe = 26, Co = 27] [2024]

1 ${[Co {(H_{2} O)}_{6}]}^{2 +}$

2 ${[Mn {(H_{2} O)}_{6}]}^{2 +}$

3 ${[Fe {(H_{2} O)}_{6}]}^{2 +}$

4 ${[Cr {(H_{2} O)}_{6}]}^{2 +}$

Want Us to Email you About Special Offers & Updates?

Complex	Electronic configuration of central metal ion without splitting	Electronic configuration after splitting	Number of unpaired electrons
${[{Co(H}_{2} {O)}_{6}]}^{2 +}$	${Co}^{2 +} = {}_{18}{[Ar]} 3 d^{7}$	$t_{2 g}^{2, 2, 1} e_{g}^{1, 1}$	3
${[{Mn(H}_{2} {O)}_{6}]}^{2 +}$	${Mn}^{2 +} = {}_{18}{[Ar]} 3 d^{5}$	$t_{2 g}^{1, 1, 1} e_{g}^{1, 1}$	5
${[{Fe(H}_{2} {O)}_{6}]}^{2 +}$	${Fe}^{2 +} = {}_{18}{[Ar]} 3 d^{6}$	$t_{2 g}^{2, 1, 1} e_{g}^{1, 1}$	4
${[{Cr(H}_{2} {O)}_{6}]}^{2 +}$	${Cr}^{2 +} = {}_{18}{[Ar]} 3 d^{4}$	$t_{2 g}^{1, 1, 1} e_{g}^{1, 0}$	4

Solution

Q. Which one of the following complexes will exhibit the least paramagnetic behaviour [Atomic number, Cr = 24, Mn = 25, Fe = 26, Co = 27] [2024]

1 [Co(H2O)6]2+

2 [Mn(H2O)6]2+

3 [Fe(H2O)6]2+

4 [Cr(H2O)6]2+

Want Us to Email you About Special Offers & Updates?

Q.
Which one of the following complexes will exhibit the least paramagnetic behaviour

[Atomic number, Cr = 24, Mn = 25, Fe = 26, Co = 27] [2024]

1 ${[Co {(H_{2} O)}_{6}]}^{2 +}$

2 ${[Mn {(H_{2} O)}_{6}]}^{2 +}$

3 ${[Fe {(H_{2} O)}_{6}]}^{2 +}$

4 ${[Cr {(H_{2} O)}_{6}]}^{2 +}$