Question

Match List I with List II. 
 

• A. A-II, B-I, C-IV, D-III
• B. A-II, B-IV, C-I, D-III
• C. A-II, B-III, C-I, D-IV
• D. A-I, B-II, C-IV, D-III

Hint:

Oxidation state calculations require balancing ligand charges with the overall charge of the complex. Carbonyl ligands are neutral and do not contribute to charge.

Answer 1

The Correct Option is A

Step 1: Oxidation Number Calculation Ni(CO)$_4$: Carbonyl (CO) is a neutral ligand. Since Ni has no charge, oxidation state is 0.
[Fe(H$_2$O)$_5$NO]$^{2+$}: NO ligand contributes +1 oxidation state. Fe must be +1 to balance the charge.
[Co(CO)$_5$]$^{2-$}: Since CO is neutral, oxidation state of Co is -2.
[Cr$_2$(CO)$_{10}$]$^{2-$}: CO is neutral, so the total oxidation state of both Cr atoms is -2. Each Cr has -1 oxidation state.
Final Answer: A-II, B-I, C-IV, D-III