The enthalpy change for the reaction `C_(2)H_(2)(g)+(5)/(2)O_(2)rarr2CO_(2)(g)+H_(2)O(g)` is known as enthalpy of

Options

A. Formation
B. Fusion
C. Vaporization
D. Combustion

Answer

To determine the enthalpy change for the reaction \( C_2H_2(g) + \frac{5}{2}O_2(g) \rightarrow 2CO_2(g) + H_2O(g) \), we need to identify the type of reaction it represents.

### Step-by-Step Solution:

1. **Identify the Reaction Type**:
The given reaction involves the combustion of acetylene (\( C_2H_2 \)). In this reaction, acetylene reacts with oxygen (\( O_2 \)) to produce carbon dioxide (\( CO_2 \)) and water vapor (\( H_2O \)).

2. **Understanding Combustion**:
Combustion reactions typically involve a hydrocarbon reacting with oxygen to produce carbon dioxide and water. This is a characteristic of combustion reactions.

3. **Enthalpy Change**:
The enthalpy change associated with this reaction is known as the enthalpy of combustion. It quantifies the energy released when one mole of a substance is burned in excess oxygen.

4. **Conclusion**:
Therefore, the enthalpy change for the reaction \( C_2H_2(g) + \frac{5}{2}O_2(g) \rightarrow 2CO_2(g) + H_2O(g) \) is known as the enthalpy of combustion.

### Final Answer:
The enthalpy change for the reaction is known as the **enthalpy of combustion**.

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