Mohr's salt, $FeSO X_{4} \cdot (NH X_{4}) X_{2} SO X_{4} \cdot 6 H X_{2} O$ , contains the octahedral ion $[Fe (H X_{2} O) X_{6}] X^{2 +}$ . Treating water as a weak-field ligand (high spin), calculate the spin-only magnetic moment of the iron centre in BM (two decimals).

Numerical answer type, answer in BM, tolerance 0.01.

Answer: 4.9 BM

The sulfate and ammonium ions balance to leave iron as Fe(II),

d^{6}

. In the high spin case

t_{2 g}^{4} e_{g}^{2}

there are

n = 4

unpaired electrons.

μ = n (n + 2) = 24 = 4.90

BM.