The metal ions that have the calculated spin-only magnetic moment value of 4.9 B.M. are : Choose the correct answer from the options given below:
- A, D and E Only
- A, B and E Only
- A, C and E Only
- B and E Only
Answer
(2) A, B and E Only
Solution
= n(n+2) B.M. = 4.9 n(n+2) = 24 n = 4 unpaired electrons
A. Cr2+: 3d4 n = 4 ✓
B. Fe2+: 3d6 n = 4 ✓
C. Fe3+: 3d5 n = 5 ( = 5.92 B.M.)
D. Co2+: 3d7 n = 3 ( = 3.87 B.M.)
E. Mn3+: 3d4 n = 4 ✓
A, B and E
Answer: (2)