Magnetic Moment Examples

Q. The “spin-only” magnetic moment, in units of Bohr magnetron $\left({\mu }_B\right)$, of $N{i}^{2+}$in aqueous solution would be

1. 0
2. 4.9
3. 1.73
4. 2.84

Q. The correct order of the spin-only magnetic moments of the following complexes is:
$\left(I\right)\left[Cr\right(H_{2}O{)}_6]B{r}_2$
$\left(II\right)N{a}_4\left[Fe\right(CN{)}_6]$
$\left(III\right)N{a}_3\left[Fe\right(C_2{O}_4{)}_3\left]\right({\Delta }_0>P)$
$\left(IV\right)\left(E{t}_{4}N{)}_2\right[CoC{l}_4]$

1. $\left(III\right)>\left(I\right)>\left(IV\right)>\left(II\right)$
2. $\left(III\right)>\left(I\right)>\left(II\right)>\left(IV\right)$
3. $\left(II\right)>\left(I\right)>\left(IV\right)>\left(III\right)$
4. $\left(I\right)>\left(IV\right)>\left(III\right)>\left(II\right)$

Q. Among the following ions which has highest paramagnetism

1. $\left[Fe\right(H_{2}O{)}_6{]}^{2+}$
2. $\left[Cr\right(H_{2}O){]}^{3+}$
3. $\left[Cu\right(H_{2}O{)}_6{]}^{2+}$
4. $\left[Zn\right(H_{2}O{)}_6{]}^{2+}$

Q. Magnetic moment 2.84 B.M. is given by (At. nos. Ni = 28, Ti = 22, Cr = 24, Co = 27)

1. $C{r}^{2+}$
2. $T{i}^{3+}$
3. $C{o}^{2+}$
4. $N{i}^{2+}$

Q.

Addition of excess aqueous ammonia to a pink coloured aqueous solution of $MC{l}_2.H_{2}O\left(x\right)andN{H}_{4}Cl$ gives an octahedral complex Y in the presence of air. In aqueous solution, complex Y behaves as 1:3 electrolyte. The reaction of X with excess HCl at room temperature results in the formation of a blue coloured complex Z. The calculated spin only magnetic moment of X and Z is 3.87 B.M., whereas it is zero for complex Y.
Among the following options, which statemet(s) is (are) correct?

1. The hybridization of the central metal ion in Y is $d^{2}s{p}^3$

2. Addition of silver nitrate to Y gives only two equivalents of silver chloride

3. When X and Z are in equilibrium at $0^{\circ },$ the colour of the solution is pink

4. Z is a tetrahedral complex
   

Q.

Among the following ions which one has the highest paramagnetism?

1. $\left[Cr\right(H_{2}O{)}_6{]}^{3+}$
2. $\left[Fe\right(H_{2}O{)}_6{]}^{2+}$
3. $\left[Cu\right(H_{2}O{)}_6{]}^{2+}$
4. $\left[Zn\right(H_{2}O{)}_6{]}^{2+}$

Q.

Among the following the lowest degree of paramagnetism per mole of the compound at 298 K will be shown by:

1. $MnS{O}_4.4H_{2}O$

2. $CuS{O}_4.5H_{2}O$

3. $FeS{O}_4.6H_{2}O$

4. $NiS{O}_4.6H_{2}O$

Q.

The pair having the same magnetic moment is :
[At. No.: Cr=24, Mn=25, Fe=26, Co=27]

1. $\left[Cr\right(H_{2}O{)}_6{]}^{2+}and[CoC{l}_4{]}^{2-}$

2. $\left[Cr\right(H_{2}O{)}_6{]}^{2+}and\left[Fe\right(H_{2}O{)}_6{]}^{2+}$
3. $\left[Mn\right(H_{2}O{)}_6{]}^{2+}and\left[Cr\right(H_{2}O{)}_6{]}^{2+}$
4. $\left[CoC{l}_4{]}^{2-}and\right[Fe(H_{2}O{)}_6{]}^{2+}$

Q.

Spin only magnetic moment of the compound $Hg\left[Co\right(SCN{)}_4]$ is

1. $\sqrt{8}$

2. $\sqrt{3}$

3. $\sqrt{24}$

4. $\sqrt{15}$

Q.

Which of the following is paramagnetic ?

1. $\left[Ni\right(CO{)}_4{]}^{2-}$

2. $\left[Fe\right(CN{)}_6{]}^{4-}$

3. $\left[Ni\right(CO{)}_4]$

4. $[Co{F}_6{]}^{3-}$