Which reagent is used to detect hydrogen in an organic compound ?

Answer

To detect hydrogen in an organic compound, we can use anhydrous copper(II) sulfate (CuSO4). Here’s a step-by-step explanation of the process:

### Step-by-Step Solution:

1. **Identify the Organic Compound**: Start with an organic compound that contains hydrogen. This could be any hydrocarbon or a compound with functional groups that include hydrogen.

2. **React with Cupric Oxide (CuO)**: The organic compound is reacted with cupric oxide (CuO). During this reaction, the hydrogen present in the organic compound reacts with CuO to produce water (H2O) and copper (Cu). The reaction can be represented as:
\[ \text{Organic Compound} + \text{CuO} \rightarrow \text{Water} + \text{Copper} \]

3. **Introduce Anhydrous Copper(II) Sulfate (CuSO4)**: After the reaction with CuO, the next step is to introduce anhydrous copper(II) sulfate (CuSO4) to the mixture.

4. **Formation of Hydrated Copper(II) Sulfate**: The water produced in the previous step will react with anhydrous CuSO4 to form hydrated copper(II) sulfate (CuSO4·5H2O). This process can be represented as:
\[ \text{CuSO4} + \text{H2O} \rightarrow \text{CuSO4·5H2O} \]

5. **Observation of Color Change**: The formation of hydrated copper(II) sulfate results in a color change. Anhydrous copper(II) sulfate is white, but when it becomes hydrated, it turns blue. This blue color indicates the presence of hydrogen in the original organic compound.

### Conclusion:
Thus, the reagent used to detect hydrogen in an organic compound is anhydrous copper(II) sulfate (CuSO4), which turns blue upon hydration.