Q15 / 150 · MHT CET 2026 (19 April Shift 1) · Chemistry
What is the oxidation state of cobalt in $[\text{Co}(\text{NH}_3)_6]^{3+}$ ?
- A$+5$
- B$+4$
- Correct answerC$+3$
- D$+2$
Solution
Let the oxidation state of cobalt be $x$.
Ammonia ($\text{NH}_3$) is a neutral ligand, so its charge is $0$.
The sum of the oxidation states of all atoms in the complex ion is equal to the net charge on the ion.
$x + 6(0) = +3$
$x = +3$
The oxidation state of cobalt in $[\text{Co}(\text{NH}_3)_6]^{3+}$ is $+3$.
Answer: $+3$
Ammonia ($\text{NH}_3$) is a neutral ligand, so its charge is $0$.
The sum of the oxidation states of all atoms in the complex ion is equal to the net charge on the ion.
$x + 6(0) = +3$
$x = +3$
The oxidation state of cobalt in $[\text{Co}(\text{NH}_3)_6]^{3+}$ is $+3$.
Answer: $+3$
Hence, the correct answer is option: 'C'.