Select Redox reaction from the following

Options

A. `Zn + CuSO_(4) to ZnSO_(4) + Cu`
B. `CaO + 2HC1 to CaC1_(2) + H_(2)O`
C. `NaOH + 2HC1 to NaC1_(2) + H_(2)O`
D. `CaCo_(3) to CaO + CO_(2)`

Answer

To determine the redox reaction from the given options, we need to analyze each reaction based on the definitions of oxidation and reduction. Here’s a step-by-step solution:

### Step-by-Step Solution:

1. **Understand Redox Reactions**:
- A redox reaction involves both oxidation (loss of electrons) and reduction (gain of electrons).
- Oxidation leads to an increase in oxidation state, while reduction leads to a decrease in oxidation state.

2. **Analyze Each Option**:
- **Option 1**:
- **Reaction**: Zn + CuSO4 → ZnSO4 + Cu
- **Oxidation States**:
- Zn: 0 (elemental state) → +2 (in ZnSO4) → **Oxidation** (losing 2 electrons)
- Cu: +2 (in CuSO4) → 0 (elemental state) → **Reduction** (gaining 2 electrons)
- **Conclusion**: This is a redox reaction because both oxidation and reduction occur.

- **Option 2**:
- **Reaction**: Ca + 2HCl → CaCl2 + H2
- **Oxidation States**:
- Ca: 0 → +2 (in CaCl2) → **Oxidation**
- Cl: -1 (in HCl) → -1 (in CaCl2) → No change
- **Conclusion**: This is a redox reaction because calcium is oxidized, but since chlorine does not change, it is not a complete redox process.

- **Option 3**:
- **Reaction**: Na + Cl2 → 2NaCl
- **Oxidation States**:
- Na: 0 → +1 (in NaCl) → **Oxidation**
- Cl: 0 → -1 (in NaCl) → **Reduction**
- **Conclusion**: This is a redox reaction because both oxidation and reduction occur.

- **Option 4**:
- **Reaction**: CaCO3 → CaO + CO2
- **Oxidation States**:
- Ca: +2 (in CaCO3) → +2 (in CaO) → No change
- C: +4 (in CO2) → +4 (in CaCO3) → No change
- **Conclusion**: This is not a redox reaction because there is no change in oxidation states.

3. **Final Selection**:
- From the analysis, **Option 1** is the only reaction that clearly demonstrates both oxidation and reduction processes, making it a redox reaction.