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 give `CO_(2)` with `NaHCO_(3)`
D. All are true

Answer

To determine which statements are true regarding the tests for various organic compounds, we will analyze each statement step by step.

### Step-by-Step Solution:

1. **Statement A: Alcohol gives red color with ceric ammonium nitrate.**
- **Analysis:** The ceric ammonium nitrate test is specifically used for aliphatic alcohols. When aliphatic alcohols are treated with ceric ammonium nitrate, a red color is produced, indicating a positive test. Therefore, this statement is correct.

2. **Statement B: Aldehyde and ketone give orange-red with DNP.**
- **Analysis:** The 2,4-Dinitrophenylhydrazine (DNP) test is used to detect carbonyl compounds, which include both aldehydes and ketones. When these compounds react with DNP, they form a hydrazone that typically appears as an orange-red precipitate. Thus, this statement is also correct.

3. **Statement C: Carboxylic acids give carbon dioxide gas with ammonium sodium bicarbonate.**
- **Analysis:** Carboxylic acids are acidic and will react with sodium bicarbonate (a weak base) to produce carbon dioxide gas, water, and a sodium salt of the acid. This reaction confirms that carboxylic acids will indeed release CO2 gas when treated with ammonium sodium bicarbonate. Therefore, this statement is correct as well.

4. **Conclusion:**
- Since all three statements (A, B, and C) are correct, the final option (D) stating that all are true is the correct answer.

### Final Answer:
All statements A, B, and C are true. Therefore, the correct answer is option D: All are true.

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