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. Dumas and Kjeldahl's method are used for the quantitative estimation of

Options

A. C and H
B. Halogen, S, And P
C. N
D. All

Answer

To solve the question regarding the quantitative estimation of elements using Dumas and Kjeldahl's methods, we will follow these steps:

### Step-by-Step Solution:

1. **Understanding Dumas Method**:
- The Dumas method is primarily used for the determination of nitrogen content in organic compounds. In this method, the sample is combusted in a high-temperature environment, and the nitrogen is converted into nitrogen gas (N₂), which can then be measured.

2. **Understanding Kjeldahl Method**:
- The Kjeldahl method is also used for the quantitative estimation of nitrogen. In this method, the organic compound is digested with concentrated sulfuric acid, which converts nitrogen into ammonium sulfate. The nitrogen content is then determined through a series of titrations.

3. **Comparison of Methods**:
- Both methods are effective for estimating nitrogen, but they have different procedures and applications. The Kjeldahl method is particularly useful for compounds that can be converted into ammonium sulfate, while the Dumas method can be applied to a broader range of organic compounds.

4. **Limitations**:
- It's important to note that the Kjeldahl method cannot be used for compounds with nitrogen in a ring structure (like pyridine), while the Dumas method can be used for a wider variety of nitrogen-containing compounds.

5. **Conclusion**:
- Based on the above understanding, both Dumas and Kjeldahl's methods are used for the quantitative estimation of nitrogen in organic compounds.

### Final Answer:
Dumas and Kjeldahl's methods are used for the quantitative estimation of **Nitrogen (N)**.

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