_____is produced when steam is passed over hot coke (`1000^@C`).

Explanation

To solve the question of what is produced when steam is passed over hot coke at 1000°C, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Reactants**:
- The reactants in this process are steam (H2O) and hot coke (which is primarily carbon, C).

2. **Identify the Reaction**:
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