Compounds I and II can be distinguished by using reagent.
`{:(" "I ," "II),("4-Amino-2methylbut-3-en-2ol","4-Amino-2,2-dimethylbut-3-yn-1-ol"):}`

Options

A. `NaNO_2//HCl`
B. `Br_2//H_2O`
C. `HCl//ZnCl_2` (anhydrous )
D. `Cu_2Cl_2 // NH_4 OH`

Explanation

To distinguish between the two compounds, 4-Amino-2-methylbut-3-en-2-ol (Compound I) and 4-Amino-2,2-dimethylbut-3-yn-1-ol (Compound II), we can use specific reagents that react differently with primary and tertiary alcohols.

### Step-by-Step Solution:

1. **Identify the Structure of Each Compound:**
- **Compound I (4-Amino-2-methylbut-3-en-2-ol):**
- It has a hydroxyl (OH) group at the second carbon, a double bond at the third carbon, and an amino (NH2) group at the fourth carbon.
- This compound is classified as a tertiary alcohol because the carbon bearing the OH group is connected to three other carbon atoms.

- **Compound II (4-Amino-2,2-dimethylbut-3-yn-1-ol):**
- It has a hydroxyl (OH) group at the first carbon, a triple bond at the third carbon, and an amino (NH2) group at the fourth carbon.
- This compound is classified as a primary alcohol because the carbon bearing the OH group is connected to only one other carbon atom.

2. **Choose the Reagent for Distinction:**
- We can use **Lucas Reagent**, which consists of concentrated hydrochloric acid (HCl) and anhydrous zinc chloride (ZnCl2). This reagent is effective in differentiating between primary and tertiary alcohols.

3. **Perform the Reaction:**
- When Lucas Reagent is added to Compound I (tertiary alcohol), it will react immediately, resulting in the formation of an alkyl chloride and producing turbidity (cloudiness).
- When Lucas Reagent is added to Compound II (primary alcohol), there will be no immediate reaction, and thus no turbidity will be observed.

4. **Conclusion:**
- By observing the reaction with Lucas Reagent, we can distinguish between the two compounds:
- **Turbidity indicates Compound I (tertiary alcohol).**
- **No turbidity indicates Compound II (primary alcohol).**

### Final Answer:
The two compounds can be distinguished by using **Lucas Reagent (HCl and ZnCl2)**.

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