Arrange the following in order of increasing reactivity towards Lucas reagent: butan-1-ol, 2-methylpropan-2-ol, butan-2-ol,

Explanation

To determine the order of increasing reactivity of butan-1-ol, butan-2-ol, and 2-methylpropan-2-ol towards Lucas reagent, we need to analyze the structure of each alcohol and classify them as primary, secondary, or tertiary alcohols.

### Step 1: Identify the type of alcohols
1. **Butan-1-ol**: This is a primary alcohol because the hydroxyl (-OH) group is attached to a carbon that is connected to only one other carbon atom.
2. **Butan-2-ol**: This is a secondary alcohol because the -OH group is attached to a carbon that is connected to two other carbon atoms.
3. **2-Methylpropan-2-ol**: This is a tertiary alcohol because the -OH group is attached to a carbon that is connected to three other carbon atoms.

### Step 2: Reactivity towards Lucas reagent
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