Which of the following is the best scientific method to test the presence of water in liquid ?

Options

A. Smell the liquids
B. Add anhydrous copper sulphate and look for a colour change
C. Taste the liquid
D. Litmus paper with the solution

Explanation

To determine the best scientific method to test for the presence of water in a liquid, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Options**: We need to evaluate the given options (A, B, C, D) to identify which method is scientifically valid for detecting water.

2. **Identify a Suitable Reagent**: One well-known reagent for detecting water is anhydrous copper(II) sulfate (CuSO4). Anhydrous copper sulfate is a white solid that can absorb water.

3. **Conduct the Test**: When anhydrous copper sulfate is added to a liquid, it will undergo a chemical change if water is present. Specifically, it will hydrate and change color from white to blue.

4. **Interpret the Results**: If the copper sulfate changes from white to blue, this indicates the presence of water in the liquid. If there is no color change, it suggests that water is not present.

5. **Select the Correct Option**: Based on the above reasoning, the best scientific method to test for water is to use anhydrous copper sulfate, which corresponds to option B (assuming option B is the one that mentions using anhydrous copper sulfate).

### Final Answer:
The best scientific method to test for the presence of water in a liquid is to add anhydrous copper sulfate and observe if it changes color from white to blue. Therefore, the correct option is **B**.

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