`underset("Calcium carbide")(CaC_(2))overset(H_(2)O)(to)(A)overset("Red hot Cu tube")(to)(B)`, Product (B) of the reaction is:

Options

A.
B.
C.
D.

Answer

To solve the question regarding the reaction of calcium carbide (CaC₂) with water (H₂O) and subsequently with a red hot copper tube, we can break it down into the following steps:

### Step 1: Reaction of Calcium Carbide with Water
1. **Identify the Reactants**: We start with calcium carbide (CaC₂) and water (H₂O).
2. **Write the Reaction**: When calcium carbide reacts with water, it produces calcium hydroxide (Ca(OH)₂) and acetylene (C₂H₂).
\[ \text{CaC}_2 + 2 \text{H}_2\text{O} \rightarrow \text{Ca(OH)}_2 + \text{C}_2\text{H}_2 \]
3. **Identify Product A**: From the above reaction, we can identify product A as calcium hydroxide (Ca(OH)₂) and acetylene (C₂H₂).

### Step 2: Reaction of Acetylene with Red Hot Copper Tube
1. **Identify the Next Step**: The acetylene (C₂H₂) produced in the first reaction is then passed through a red hot copper tube.
2. **Write the Reaction**: When acetylene is heated in the presence of red hot copper, it undergoes a process called dehydrogenation, leading to the formation of benzene (C₆H₆).
\[ 2 \text{C}_2\text{H}_2 \xrightarrow{\text{Red hot Cu}} \text{C}_6\text{H}_6 \]
3. **Identify Product B**: Thus, the product B from this reaction is benzene (C₆H₆).

### Conclusion
The final answer is that product B of the reaction is benzene (C₆H₆).

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