Which of the following reaction increases, production of dihydrogen from synthesis gas ?

Options

A. `CH_(4(g))+H_(2)O_((g))overset(1270 K)underset(Ni)rarr CO_((g))+3H_(2(g))`
B. `C_((s))+H_(2)O_((g))overset(1270 K)rarr CO_((g))+H_(2(g))`
C. `CO_((g))+H_(2)O_((g))overset(673 K)underset("Catalyst")rarr CO_(2(g))+H_(2(g))`
D. `C_(2)H_(6(g))+2H_(2(g))O overset(1270 K)underset(Ni)rarr 2CO_((g))+5H_(2(g))`

Explanation

To determine which reaction increases the production of dihydrogen from synthesis gas, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Synthesis Gas Composition**:
- Synthesis gas (syngas) primarily consists of carbon monoxide (CO) and hydrogen (H2).

2. **Identify the Reaction for Dihydrogen Production**:
- To increase the production of dihydrogen, we can react carbon monoxide (CO) present in the synthesis gas with steam (H2O).

3. **Write the Reaction**:
- The reaction can be represented as:
\[ \text{CO} + \text{H}_2\text{O} \rightarrow \text{CO}_2 + \text{H}_2 \]
- This reaction shows that carbon monoxide reacts with steam to produce carbon dioxide (CO2) and dihydrogen (H2).

4. **Catalyst and Conditions**:
- This reaction typically requires a catalyst for efficient conversion. A common catalyst used is iron chromate (Fe2CrO4) and the reaction is conducted at a high temperature, around 673 Kelvin.

5. **Conclusion**:
- From the analysis, the reaction that increases the production of dihydrogen from synthesis gas is:
\[ \text{CO} + \text{H}_2\text{O} \text{ (steam)} \]
- Therefore, the correct answer is option C: CO + H2O.