Which of the following is true ?

Options

A. Alcohol give red colour with cerric ammonium nitrate
B. Aldehyde and ketone give orange red colour with, `2,4` - DNP
C. RCOOH gives `CO_(2)` with `NaHCO_(3)`
D. All are true

Answer

To determine which of the statements is true, let's analyze each statement step by step based on the information provided in the video transcript.

### Step-by-Step Solution:

1. **Statement 1: Alcohol gives red color with ceric ammonium nitrate.**
- Ceric ammonium nitrate (CAN) reacts with alcohols to form a red complex. The reaction can be represented as:
\[ \text{Alcohol (ROH)} + \text{CAN} \rightarrow \text{Red complex (CENO}_3\text{O}_4) + \text{Products} \]
- Since the formation of a red complex indicates a positive reaction, this statement is **true**.

2. **Statement 2: Aldehyde and ketone give orange-red color with 2,4-DNP.**
- 2,4-Dinitrophenylhydrazine (2,4-DNP) reacts with aldehydes and ketones to form yellow, orange, or red precipitates known as 2,4-dinitrophenylhydrazones. The general reaction can be represented as:
\[ \text{Aldehyde/Ketone} + \text{2,4-DNP} \rightarrow \text{2,4-Dinitrophenylhydrazone (colored precipitate)} + \text{H}_2\text{O} \]
- Since the formation of colored precipitates confirms the presence of aldehydes or ketones, this statement is also **true**.

3. **Statement 3: Carboxylic acids react with sodium bicarbonate to give CO2.**
- Carboxylic acids react with sodium bicarbonate (NaHCO3) to produce carbon dioxide (CO2), water (H2O), and a salt. The reaction can be represented as:
\[ \text{R-COOH} + \text{NaHCO}_3 \rightarrow \text{R-COONa} + \text{CO}_2 + \text{H}_2\text{O} \]
- The evolution of CO2 gas indicates a positive reaction, making this statement **true**.

4. **Conclusion:**
- Since all three statements have been verified as true, the final conclusion is that **all statements are true**.

### Final Answer:
All of the statements provided are true.

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