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QJEEM23Chd2d2: JEE Main 2023 Chemistry - Class 12 JEEM23Chd2d2 Solution: The spin only magnetic moment of complexes is _________ B.M.…

The spin only magnetic moment of [Mn(H2O)6]2+\left[\mathrm{Mn}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{2+} complexes is _________ B.M. (Nearest integer)

(Given : Atomic no. of Mn is 25)

Step-by-Step Verified Solution

The spin only magnetic moment of the [Mn(H2O)6]2+\left[\mathrm{Mn}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{2+} complex can be calculated using the formula:

μ = n(n+2)\sqrt {n\left( {n + 2} \right)} Bohr magnetons

Where n is the number of unpaired electrons in the complex. To find the number of unpaired electrons in [Mn(H2O)6]2+\left[\mathrm{Mn}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{2+} , we can use the electron configuration of the Mn ion:

For Mn2+ : 1s2 2s2 2p6 3s2 3p6 3d5

From the electron configuration, we can see that Mn2+ has 5 unpaired electrons. Thus, the spin only magnetic moment of [Mn(H2O)6]2+\left[\mathrm{Mn}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{2+} is:

μ = 5(5+2)\sqrt {5\left( {5 + 2} \right)} = 35\sqrt {35} = 5.9 Bohr Magnetons

The nearest integer to 5.9 is 6.

Hence, the spin only magnetic moment of [Mn(H2O)6]2+\left[\mathrm{Mn}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{2+} is 6 Bohr magnetons.

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