Quantitative estimatin of `C,H` and extra elements (e.g., N.S.P., and halogens) is carried out by Liebig's combustion, Carius, Dumas, and Kjeldahl's method.
Q. Liebig's combustion method is used for the quantitative estimation of :

Options

A. C and H
B. Halogens
C. S and P
D. N

Answer

### Step-by-Step Solution:

1. **Understanding Liebig's Combustion Method**:
- Liebig's combustion method is a technique used to determine the amounts of carbon and hydrogen in an organic compound.

2. **Process of Combustion**:
- A known mass of the organic compound is taken and combusted in the presence of pure air (oxygen).
- During combustion, the carbon in the organic compound is oxidized to form carbon dioxide (CO₂), and the hydrogen is oxidized to form water (H₂O).

3. **Products of Combustion**:
- The products of this combustion reaction are carbon dioxide and water.
- The amount of CO₂ produced indicates the amount of carbon in the original compound, while the amount of H₂O produced indicates the amount of hydrogen.

4. **Calculating Percentages**:
- By measuring the masses of the produced carbon dioxide and water, we can calculate the percentage of carbon and hydrogen in the original organic compound using stoichiometric relationships.

5. **Conclusion**:
- Therefore, Liebig's combustion method is specifically used for the quantitative estimation of carbon (C) and hydrogen (H) in organic compounds.

### Final Answer:
Liebig's combustion method is used for the quantitative estimation of **carbon and hydrogen**.

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