In Dumas' method, the gas (or vapor) which is collected in the nitrometer is

Options

A. `N_(2)`
B. `NO`
C. `NH_(3)`
D. `H_(2)`

Answer

**Step-by-Step Text Solution:**

1. **Understanding Dumas' Method**: Dumas' method is a technique used to determine the nitrogen content in organic compounds. It involves the combustion of the organic compound in the presence of cupric oxide (CuO).

2. **Reaction Process**: When the organic compound is heated with cupric oxide, the carbon (C) and hydrogen (H) in the compound are oxidized. The carbon is converted to carbon dioxide (CO2), and the hydrogen is converted to water (H2O).

3. **Nitrogen Behavior**: During this process, nitrogen (N) present in the organic compound is released as a free gas. Any nitrogen oxides that might form during the combustion are reduced back to nitrogen gas (N2).

4. **Collection of Gases**: The gases produced (CO2, H2O, and N2) are collected in a device called a nitrometer. The nitrometer is typically filled with an aqueous solution of potassium hydroxide (KOH).

5. **Absorption of Gases**: The potassium hydroxide solution absorbs the carbon dioxide (CO2) and water vapor (H2O), leaving behind only the nitrogen gas (N2) in the nitrometer.

6. **Measurement of Nitrogen**: The volume of nitrogen gas collected in the nitrometer is measured. This volume can be used to calculate the percentage of nitrogen in the original organic compound.

7. **Conclusion**: Therefore, the gas collected in the nitrometer during Dumas' method is nitrogen (N2).

**Final Answer**: The gas (or vapor) which is collected in the nitrometer is nitrogen (N2).

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