Arrange the following in the order of increasing acidic strength :
` (I ) CH_3 CHFCOOH `
`(ii ) CH_3 CH_2 COOH `
`(iii ) CH_3 CF_2 COOH `

Explanation

To determine the order of increasing acidic strength of the given carboxylic acids, we need to analyze the stability of their conjugate bases. The more stable the conjugate base, the stronger the acid.

### Step-by-Step Solution:

1. **Identify the Compounds**:
- (I) CH₃CHFCOOH (2-fluoropropanoic acid)
- (II) CH₃CH₂COOH (propanoic acid)
- (III) CH₃CF₂COOH (2,2-difluoropropanoic acid)
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