Coordination Compounds: JEE Main Chemistry Question with Solution

The sum of oxidation state of the metals in

\mathrm{Fe}(\mathrm{CO})_{5}

\mathrm{VO}^{2+}

and

\mathrm{WO}_{3}

\underline{\quad\quad\quad}

Your answer stays private

What feels right?

No score. Commit to your first instinct. We’ll show what your mind noticed and what it missed.

Type the value - units or words beside it are fine.

✓ Source and academic review

Question type: Numerical
Exam relevance: JEE Main · Chemistry
Concepts assessed: Chemistry
Academic status: Reviewed by official_key
Source: pyq
Editorial review: 7 September 2026

Quick checks

Students also ask

Why is the oxidation state of Fe in Fe(CO)5 equal to 0?

Carbon monoxide (CO) is a neutral molecule with zero formal charge. Therefore, the net charge on the complex (0) belongs entirely to Fe. This makes its oxidation state 0.

Answer

The oxidation states of the metals are 0 in $\mathrm{Fe}(\mathrm{CO})_5$ , +4 in $\mathrm{VO}^{2+}$ , and +6 in $\mathrm{WO}_3$ , giving a total sum of 10.

Why each option works or fails

Step-by-step solution

given: Given species are $\mathrm{Fe(CO)_5}$ , $\mathrm{VO^{2+}}$ , and $\mathrm{WO_3}$ .
find: We need to find the sum of the oxidation states of the transition metals ( $\mathrm{Fe}$ , $\mathrm{V}$ , and $\mathrm{W}$ ) in the given species.
strategise: Determine the oxidation state of each metal individually by assigning standard oxidation numbers to ligands/atoms (neutral $\mathrm{CO} = 0$ , oxide $\mathrm{O}^{2-} = -2$ ) and equating the algebraic sum of oxidation numbers to the net charge of each species.
execute: 1. In $\mathrm{Fe(CO)_5}$ : $\mathrm{CO}$ is a neutral ligand (charge 0). Thus, $\text{O.S. of Fe} + 5(0) = 0 \implies \text{O.S.}(\mathrm{Fe}) = 0$ . 2. In $\mathrm{VO^{2+}}$ : Oxygen has an oxidation state of $-2$ . Thus, $\text{O.S. of V} + (-2) = +2 \implies \text{O.S.}(\mathrm{V}) = +4$ . 3. In $\mathrm{WO_3}$ : Oxygen has an oxidation state of $-2$ . Thus, $\text{O.S. of W} + 3(-2) = 0 \implies \text{O.S.}(\mathrm{W}) = +6$ . Sum of oxidation states $= 0 + 4 + 6 = 10$ .
verify: Check: $\mathrm{Fe}$ is in a homoleptic carbonyl complex (always 0), $\mathrm{V}$ in vanadyl ion $\mathrm{VO}^{2+}$ is in $+4$ state, $\mathrm{W}$ in tungsten trioxide is in group-maximum $+6$ state. Sum $= 0 + 4 + 6 = 10$ . Everything matches chemistry fundamentals.

Coordination Compounds: JEE Main Chemistry Question with Solution

What feels right?

The oxidation states of the metals are 0 in $\mathrm{Fe}(\mathrm{CO})_5$ , +4 in $\mathrm{VO}^{2+}$ , and +6 in $\mathrm{WO}_3$ , giving a total sum of 10.

Why each option works or fails

Solution

01given

02find

03strategise

04execute

✓verify

Students also ask

Coordination Compounds: JEE Main Chemistry Question with Solution

The oxidation states of the metals are 0 in Fe(CO)5\mathrm{Fe}(\mathrm{CO})_5Fe(CO)5​, +4 in VO2+\mathrm{VO}^{2+}VO2+, and +6 in WO3\mathrm{WO}_3WO3​, giving a total sum of 10.

01given

02find

03strategise

04execute

✓verify

Students also ask

The oxidation states of the metals are 0 in $\mathrm{Fe}(\mathrm{CO})_5$ , +4 in $\mathrm{VO}^{2+}$ , and +6 in $\mathrm{WO}_3$ , giving a total sum of 10.