Three alcohols
(i) `CH_3CH_2CH_2OH,`
(ii) `CH_3-CHOH-CH_3and`
(iii) `CH_3-C(CH_3)(OH)-CH_3`
were treated seperately with Lucas reagent (Conc. `HCl+ZnCl_2`) . What results do you expect at room temperature.

Options

A. (i) reacts is about 5 minutes , (ii) reacts in about 15 minutes and (ii) not at all
B. (iii) reacts immediately , (ii) reacts in about 5 minutes and (i) not at all
C. (ii) and (iii) react immediately and (i) in about 5 minutes
D. (i) reacts immediately , (ii) reacts in about 5 minutes and (iii) not at all

Answer

To solve the problem, we need to analyze the behavior of the three given alcohols when treated with Lucas reagent (a mixture of concentrated HCl and ZnCl₂). The Lucas test is used to differentiate between primary, secondary, and tertiary alcohols based on their reactivity.

### Step-by-step Solution:

1. **Identify the Type of Alcohols:**
- (i) `CH₃CH₂CH₂OH` is a **primary alcohol** (1-butanol).
- (ii) `CH₃-CHOH-CH₃` is a **secondary alcohol** (2-propanol).
- (iii) `CH₃-C(CH₃)(OH)-CH₃` is a **tertiary alcohol** (2-methyl-2-propanol).

2. **Understand the Lucas Test:**
- The Lucas reagent (conc. HCl + ZnCl₂) reacts with alcohols to form alkyl halides.
- The reactivity order of alcohols with Lucas reagent is: **tertiary > secondary > primary**.
- Tertiary alcohols react quickly (immediate turbidity), secondary alcohols react within a few minutes (about 5 minutes), and primary alcohols do not react at room temperature.

3. **Predict the Results for Each Alcohol:**
- **For (i) `CH₃CH₂CH₂OH` (Primary Alcohol):**
- Expected Result: No turbidity at room temperature.
- **For (ii) `CH₃-CHOH-CH₃` (Secondary Alcohol):**
- Expected Result: Turbidity appears within about 5 minutes.
- **For (iii) `CH₃-C(CH₃)(OH)-CH₃` (Tertiary Alcohol):**
- Expected Result: Immediate turbidity.

4. **Summarize the Results:**
- **Primary Alcohol (i)**: No turbidity at room temperature.
- **Secondary Alcohol (ii)**: Turbidity appears in about 5 minutes.
- **Tertiary Alcohol (iii)**: Immediate turbidity.

### Final Results:
- (i) No turbidity (Primary Alcohol)
- (ii) Turbidity in about 5 minutes (Secondary Alcohol)
- (iii) Immediate turbidity (Tertiary Alcohol)