In which of the compounds oxygen does not exhibit oxidation state (-2)?

Options

A. `CsO_(2)`
B. `K_(2)O_(2)`
C. `OF_(2)`
D. `Cl_(2)O`

Answer

To determine in which of the given compounds oxygen does not exhibit an oxidation state of -2, we will analyze each compound one by one.

### Step 1: Analyze CSO2 (Cesium Dioxide)
- **Oxidation State Calculation**:
- Cesium (Cs) has an oxidation state of +1.
- Let the oxidation state of oxygen be \( x \). Since there are two oxygen atoms, the equation can be set up as:
\[ +1 + 2x = 0 \]
- Solving for \( x \):
\[ 2x = -1 \implies x = -\frac{1}{2} \]
- **Conclusion**: In CSO2, oxygen has an oxidation state of -1/2, not -2.

### Step 2: Analyze K2O2 (Potassium Peroxide)
- **Oxidation State Calculation**:
- Potassium (K) has an oxidation state of +1. Thus, for two potassium atoms:
\[ 2(+1) + 2x = 0 \]
- Solving for \( x \):
\[ 2x + 2 = 0 \implies 2x = -2 \implies x = -1 \]
- **Conclusion**: In K2O2, oxygen has an oxidation state of -1, not -2.

### Step 3: Analyze OF2 (Oxygen Difluoride)
- **Oxidation State Calculation**:
- Fluorine (F) has an oxidation state of -1. For two fluorine atoms:
\[ x + 2(-1) = 0 \]
- Solving for \( x \):
\[ x - 2 = 0 \implies x = +2 \]
- **Conclusion**: In OF2, oxygen has an oxidation state of +2, not -2.

### Step 4: Analyze Cl2O (Dichlorine Monoxide)
- **Oxidation State Calculation**:
- Chlorine (Cl) has an oxidation state of +1. For two chlorine atoms:
\[ 2x + y = 0 \]
- Since there are two chlorine atoms:
\[ 2x + 2 = 0 \implies x = -2 \]
- **Conclusion**: In Cl2O, oxygen has an oxidation state of -2.

### Final Conclusion
The compounds in which oxygen does not exhibit an oxidation state of -2 are:
1. CSO2 (Cesium Dioxide) - Oxidation state of oxygen is -1/2.
2. K2O2 (Potassium Peroxide) - Oxidation state of oxygen is -1.
3. OF2 (Oxygen Difluoride) - Oxidation state of oxygen is +2.

Thus, the answer is **CSO2, K2O2, and OF2**.

---