An organic liquid 'A' containing C,H and O with boiling point `78^(@)C`, possessing a rather pleasant odous. On heating with concentrated sulphuric acid gives a gaseous product 'B' with the empirical formula `CH_(2)` 'B' decolourises bromine water as well as alkaline permanganate solution and takes up one mole of `H_(2)` (per mole of B) in presence of finely divided nickel at high temperature. Identify the substances A and B.

Explanation

To solve the problem, we need to identify the organic liquid 'A' and the gaseous product 'B' based on the clues provided in the question. Let's break it down step by step.

### Step 1: Analyze the properties of compound A
- **Given:** Compound A has a boiling point of 78°C and a pleasant odor.
- **Conclusion:** The boiling point and pleasant odor suggest that compound A could be ethanol (C2H5OH), which has a boiling point of approximately 78°C and is known for its pleasant smell.

### Step 2: Determine the reaction of compound A with concentrated sulfuric acid
- **Given:** Heating compound A with concentrated sulfuric acid produces a gaseous product B.
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