In the reaction `2KMnO_4 + 5H_2C_2O_4 + 3H_2SO_4 to 2MnSO_4 + 10CO_2 + 8H_2O + K_2 SO_4 `
Mn shows which type of reaction?

Options

A. Addition
B. Substitution
C. Oxidation
D. Reduction

Explanation

To determine the type of reaction that manganese (Mn) undergoes in the given reaction, we need to analyze the oxidation states of manganese in the reactants and products.

### Step-by-Step Solution:

1. **Write the Reaction:**
The reaction given is:
\[ 2KMnO_4 + 5H_2C_2O_4 + 3H_2SO_4 \rightarrow 2MnSO_4 + 10CO_2 + 8H_2O + K_2SO_4 \]

2. **Identify the Oxidation State of Manganese in KMnO4:**
- In potassium permanganate (KMnO4), potassium (K) has an oxidation state of +1.
- Oxygen (O) has an oxidation state of -2. Since there are 4 oxygen atoms, their total contribution is \(4 \times (-2) = -8\).
- Let the oxidation state of manganese (Mn) be \(x\). The overall charge of the compound is neutral (0).
- Therefore, we can set up the equation:
\[ +1 + x + (-8) = 0 \]
Simplifying this gives:
\[ x - 7 = 0 \implies x = +7 \]
- Thus, the oxidation state of Mn in KMnO4 is +7.

3. **Identify the Oxidation State of Manganese in MnSO4:**
- In manganese sulfate (MnSO4), the sulfate ion (SO4) has an oxidation state of -2.
- Let the oxidation state of manganese (Mn) again be \(y\). The overall charge of the compound is neutral (0).
- Therefore, we can set up the equation:
\[ y + (-2) = 0 \]
Simplifying this gives:
\[ y = +2 \]
- Thus, the oxidation state of Mn in MnSO4 is +2.

4. **Compare the Oxidation States:**
- In KMnO4, Mn has an oxidation state of +7.
- In MnSO4, Mn has an oxidation state of +2.
- The change in oxidation state from +7 to +2 indicates that manganese is gaining electrons.

5. **Determine the Type of Reaction:**
- Since the oxidation state of manganese decreases from +7 to +2, this process is known as reduction (the gain of electrons).
- Therefore, the reaction involving manganese can be classified as a **reduction reaction**.

### Conclusion:
Mn shows a **reduction reaction** in the given chemical equation.

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