Distinguish between the following :
(i) `CH_(3)-CO-CH_(2)CH_(3)` and `CH_(3)-CH_(2)-CH_(2)-CHO`
(ii) Ethanal and ethanoic acid.

Explanation

To distinguish between the given compounds, we will analyze each pair separately.

### (i) Distinguishing between `CH₃-CO-CH₂CH₃` and `CH₃-CH₂-CH₂-CHO`

1. **Identify the Structures:**
- The first compound, `CH₃-CO-CH₂CH₃`, is a ketone (specifically, 2-pentanone).
- The second compound, `CH₃-CH₂-CH₂-CHO`, is an aldehyde (specifically, butanal).

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