Answer the following questions with respect to the solutions marked 'A' and 'B' having pH values 4 and 10 respectively.
Which solution will give a red colour with methyl orange?

Answer

To determine which solution will give a red color with methyl orange, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the pH values of the solutions**:
- Solution A has a pH of 4.
- Solution B has a pH of 10.

2. **Understand the nature of the solutions based on pH**:
- A pH value less than 7 indicates an acidic solution. Therefore, Solution A (pH 4) is acidic.
- A pH value greater than 7 indicates a basic (or alkaline) solution. Therefore, Solution B (pH 10) is basic.

3. **Know the behavior of methyl orange as an indicator**:
- Methyl orange is an acid-base indicator that changes color depending on the pH of the solution.
- It appears red in acidic solutions (pH < 3.1) and transitions to orange and then yellow as the solution becomes less acidic and eventually basic (pH > 4.4).

4. **Determine which solution will give a red color with methyl orange**:
- Since Solution A is acidic (pH 4), it will cause methyl orange to turn red.
- Solution B, being basic (pH 10), will not turn red; it will be yellow.

5. **Conclusion**:
- Therefore, the solution that will give a red color with methyl orange is Solution A.

### Final Answer:
Solution A will give a red color with methyl orange.

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