Arrange the following in the increasing order of `pK_a` values:
` CH_3 COOH ,CICH_2 COOH ,Cl_2 CHCOOH ,Cl_3 C COOH`

Explanation

To determine the increasing order of \( pK_a \) values for the compounds \( CH_3COOH \), \( ClCH_2COOH \), \( Cl_2CHCOOH \), and \( Cl_3CCOOH \), we need to analyze their acidity. The \( pK_a \) value is inversely related to the acidity of a compound; a lower \( pK_a \) value indicates a stronger acid.

### Step-by-Step Solution:

1. **Identify the Compounds**:
- \( CH_3COOH \) (Acetic acid)
- \( ClCH_2COOH \) (Chloroacetic acid)
- \( Cl_2CHCOOH \) (Dichloroacetic acid)
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