By the addition of CO and `H_(2)O` on ethyne, the following is obtained -

Options

A. Propenoic acid
B. Propanal
C. 2-Propenoic acid
D. None of these

Answer

To solve the question regarding the addition of carbon monoxide (CO) and water (H₂O) to ethyne (C₂H₂), we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Reactants**:
- The reactants in this reaction are ethyne (C₂H₂), carbon monoxide (CO), and water (H₂O).

2. **Understand the Structure of Ethyne**:
- Ethyne has the molecular structure of CH≡CH, which indicates a triple bond between the two carbon atoms.

3. **Set Up the Reaction**:
- The reaction can be written as:
\[ \text{C}_2\text{H}_2 + \text{CO} + \text{H}_2\text{O} \xrightarrow{\text{Ni catalyst}} \text{Product} \]

4. **Identify the Catalyst**:
- A nickel (Ni) catalyst is used to facilitate the reaction.

5. **Determine the Product**:
- The addition of CO and H₂O to ethyne in the presence of a nickel catalyst leads to the formation of propanoic acid (C₂H₅COOH). The reaction involves the conversion of the triple bond to a double bond and the addition of the carbonyl (C=O) and hydroxyl (–OH) groups.

6. **Final Product**:
- The final product of the reaction is propanoic acid (C₂H₅COOH).

### Final Answer:
The product obtained by the addition of CO and H₂O to ethyne is **propanoic acid (C₂H₅COOH)**.

---