10 " mL of " a gaseous hydrocarbon is exploded with 100 " mL of " oxygen. The residual gas on cooling is found to measure 95 mL, of which 20 mL is absorbed by caustic soda and the remaining by alkaline pyrogallol. The formula of the hydrocarbon is
(a). `CH_4`.
(b). `C_2H_6`
(c). `C_2H_4`
(d). `C_2H_2`

Explanation

To determine the formula of the hydrocarbon, we will follow these steps:

### Step 1: Analyze the Reaction
The reaction between the hydrocarbon (CₓHᵧ) and oxygen (O₂) can be represented as:
\[ CₓHᵧ + \left( x + \frac{y}{4} \right) O₂ \rightarrow x CO₂ + \frac{y}{2} H₂O \]

### Step 2: Identify the Given Volumes
- Volume of hydrocarbon = 10 mL
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