Arrange benzene, n-hexane and ethyne in decreasing order ofacidic behaviour.

Explanation

To arrange benzene, n-hexane, and ethyne in decreasing order of acidic behavior, we need to analyze the acidic hydrogens present in each compound and the hybridization of the carbon atoms to which these hydrogens are attached.

### Step 1: Identify the hybridization of the carbon atoms in each compound
- **Benzene (C6H6)**: The carbon atoms in benzene are sp² hybridized. Each carbon is bonded to one hydrogen atom.
- **n-Hexane (C6H14)**: The carbon atoms in n-hexane are sp³ hybridized. Each carbon is bonded to two or three hydrogen atoms.
- **Ethyne (C2H2)**: The carbon atoms in ethyne are sp hybridized. Each carbon is bonded to one hydrogen atom.

### Step 2: Determine the s-character of each hybridization
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