Amongst the following identify the species with an atom in oxidation state : `CrO_(2)Cl_(2), MnO_(4)^(-), Cr(CN)_(6)^(3-), NiF_(6)^(2-)`

Explanation

To determine the oxidation states of the elements in the given species, we will analyze each compound step by step.

### Step 1: Analyze CrO₂Cl₂
1. **Assign variables**: Let the oxidation state of chromium (Cr) be \( x \).
2. **Assign known oxidation states**: Oxygen (O) has an oxidation state of -2, and chlorine (Cl) has an oxidation state of -1.
3. **Set up the equation**: The compound is neutral, so the sum of the oxidation states must equal 0.
\[
x + 2(-2) + 2(-1) = 0
...