JEE Mains · Chemistry · STD 12 - 4. d and f- block elements
The metal ions that have the calculated spin only magnetic moment value of 4.9 B.M. are _______.
A. \(\mathrm{Cr}^{2+}\)
B. \(\mathrm{Fe}^{2+}\)
C. \(\mathrm{Fe}^{3+}\)
D. \(\mathrm{Co}^{2+}\)
E. \(\mathrm{Mn}^{3+}\)
Choose the correct answer from the options given below.
- A A, C and E only
- B A, D and E only
- C B and E only
- D A, B and E only
Answer & Solution
Correct Answer
(D) A, B and E only
Step-by-step Solution
Detailed explanation
Given magnetic moment \(=4.9\) B.M. We know M.M \(=\sqrt{\mathrm{n}(\mathrm{n}+2)}\) B.M. Where, \(\mathrm{n} \rightarrow\) No. of unpaired \(\mathrm{e}^{-}\) \(4.9=\sqrt{\mathrm{n}(\mathrm{n}+2)}\) We get \(\mathrm{n}=4\) (A)…
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