The correct decreasing order of spin only magnetic moment values (BM) of Cu+, Cu2+, Cr2+ and Cr3+ ions is :
- Cr3+ > Cr2+ > Cu+ > Cu2+
- Cu+ > Cu2+ > Cr3+ > Cr2+
- Cr2+ > Cr3+ > Cu2+ > Cu+
- Cu2+ > Cu+ > Cr2+ > Cr3+
Answer
(3) Cr2+ > Cr3+ > Cu2+ > Cu+
Solution
= n(n+2) BM
Cr2+: 3d4, n = 4 = 24 = 4.90 BM
Cr3+: 3d3, n = 3 = 15 = 3.87 BM
Cu2+: 3d9, n = 1 = 3 = 1.73 BM
Cu+: 3d10, n = 0 = 0
Cr2+ > Cr3+ > Cu2+ > Cu+
Answer: (3)