Lieberman test is given by which of the following

Options

A. `CH_3-CH_2-COOH`
B. `H_3C-underset(CH_3)underset(|)overset(CH_3)overset(|)C-OH`
C.
D.

Answer

To solve the question regarding the Liebermann test, let's break down the information step by step.

### Step 1: Understanding the Liebermann Test
The Liebermann test is a chemical test used to detect the presence of phenolic compounds, particularly cholesterol. It is based on the reaction of phenols with nitrous acid (HNO2) to form colored compounds.

**Hint:** Remember that the Liebermann test is specifically used for detecting phenolic compounds.

### Step 2: Reaction Conditions
The test involves the reaction of phenol with sodium nitrite (NaNO2) in the presence of hydrochloric acid (HCl) or dilute sulfuric acid (H2SO4). This reaction introduces a nitroso group (-N=O) to the phenolic compound.

**Hint:** Identify the reagents involved in the Liebermann test: NaNO2 and an acid (HCl or H2SO4).

### Step 3: Formation of Endophenol
When phenol reacts with NaNO2 in acidic conditions, it forms a compound known as endophenol, which exhibits a red coloration. This is due to the formation of a nitroso derivative of phenol.

**Hint:** The red coloration is a key indicator of the presence of phenolic compounds in the Liebermann test.

### Step 4: Reaction with Sodium Hydroxide
If the endophenol is treated with excess sodium hydroxide (NaOH), it forms a blue-colored complex. This blue color indicates a positive result for the Liebermann test.

**Hint:** The change from red to blue upon adding NaOH is crucial for interpreting the test results.

### Step 5: Conclusion
The Liebermann test is specifically given by phenolic compounds. Therefore, the answer to the question is that the Liebermann test is given by phenol.

**Final Answer:** The Liebermann test is given by phenol.