Identify the correct statements with reference to the given reaction
`P_(4)+3OH^(-)+3H_(2)OtoPH_(3)+3H_(2)PO_(2)^(-)`

Options

A. Phosphorus is undergoing reduction only
B. Phosphorus is undergoing oxidation only
C. Phosphorus is undergoing oxidation as well as reduction
D. Hydrogen is undergoing neither oxidation nor reduction

Explanation

To solve the problem, we will analyze the given reaction and determine the oxidation states of the elements involved. The reaction is:

\[ P_4 + 3OH^- + 3H_2O \rightarrow PH_3 + 3H_2PO_2^- \]

### Step 1: Assign Oxidation States
1. **For \( P_4 \)**: In its elemental form, the oxidation state of phosphorus (P) is 0.
2. **For \( OH^- \)**: The oxidation state of oxygen (O) is -2 and hydrogen (H) is +1.
3. **For \( H_2O \)**: Each hydrogen (H) has an oxidation state of +1 and oxygen (O) is -2.
4. **For \( PH_3 \)**: Let the oxidation state of phosphorus be \( x \). The equation is:
\[ x + 3(+1) = 0 \implies x + 3 = 0 \implies x = -3 \]
So, the oxidation state of phosphorus in \( PH_3 \) is -3.
5. **For \( H_2PO_2^- \)**: Let the oxidation state of phosphorus be \( y \). The equation is:
\[ y + 2(+1) + 2(-2) = -1 \implies y + 2 - 4 = -1 \implies y - 2 = -1 \implies y = +1 \]
So, the oxidation state of phosphorus in \( H_2PO_2^- \) is +1.

### Step 2: Determine Changes in Oxidation States
- **Phosphorus**:
- Changes from 0 in \( P_4 \) to -3 in \( PH_3 \) (reduction).
- Changes from 0 in \( P_4 \) to +1 in \( H_2PO_2^- \) (oxidation).

- **Hydrogen**:
- The oxidation state of hydrogen remains +1 in all species (no change).

### Step 3: Identify Oxidation and Reduction
- **Oxidation**: Increase in oxidation state (loss of electrons).
- **Reduction**: Decrease in oxidation state (gain of electrons).

From the analysis:
- Phosphorus is both oxidized (to +1 in \( H_2PO_2^- \)) and reduced (to -3 in \( PH_3 \)).
- Hydrogen does not undergo any change in oxidation state.

### Conclusion
Now, let's evaluate the statements:
1. **Phosphorus is undergoing reduction only**: **False** (it undergoes both oxidation and reduction).
2. **Phosphorus is undergoing oxidation only**: **False** (it undergoes both oxidation and reduction).
3. **Phosphorus is undergoing oxidation as well as reduction**: **True**.
4. **Hydrogen is undergoing neither oxidation nor reduction**: **True**.

Thus, the correct statements are **3 and 4**.