In a reaction
`H_(2)O("steam")+C("glowing") to CO+H_(2)`

Options

A. `H_(2)O` is the reducing agent
B. `H_(2)O` is the oxidising agent
C. carbon is the oxidising agent
D. oxidation-reduction does not occur

Answer

To solve the question regarding the reaction of steam (H₂O) with glowing carbon (C) to produce carbon monoxide (CO) and hydrogen gas (H₂), we will analyze the oxidation states of the elements involved in the reaction.

### Step-by-Step Solution:

1. **Write the balanced chemical equation:**
The reaction can be represented as:
\[ \text{H}_2\text{O (steam)} + \text{C (glowing)} \rightarrow \text{CO} + \text{H}_2 \]

2. **Determine the oxidation states of each element:**
- In H₂O, the oxidation state of H is +1 and O is -2.
- In C (glowing), the oxidation state of C is 0.
- In CO, the oxidation state of C is +2 and O is -2.
- In H₂, the oxidation state of H is 0.

3. **Identify changes in oxidation states:**
- For H in H₂O:
- Changes from +1 in H₂O to 0 in H₂ (reduction).
- For C:
- Changes from 0 in C to +2 in CO (oxidation).

4. **Determine the oxidizing and reducing agents:**
- The substance that is reduced (gains electrons) is the oxidizing agent. Here, H₂O is reduced (H goes from +1 to 0), so H₂O acts as the oxidizing agent.
- The substance that is oxidized (loses electrons) is the reducing agent. Here, C is oxidized (C goes from 0 to +2), so C acts as the reducing agent.

5. **Conclusion:**
- Based on the analysis, we conclude that H₂O is the oxidizing agent and C is the reducing agent. Therefore, the correct option is B.