Aqua regia is a mixture of:

Options

A. Conc. `HNO_3` and conc. `H_2SO_4`
B. Conc. HCl and conc. `H_2SO_4` in the ratio of `3:1`
C. Conc. HCl and conc. `HNP_3` in the ratio of `3:1`
D. None of these

Answer

**Step-by-Step Solution:**

1. **Understanding Aqua Regia**: Aqua regia is a highly corrosive mixture that is known for its ability to dissolve noble metals like gold and platinum.

2. **Identifying the Components**: Aqua regia is composed of two strong acids: hydrochloric acid (HCl) and nitric acid (HNO3).

3. **Determining the Ratio**: The typical ratio of hydrochloric acid to nitric acid in aqua regia is 3:1. This means that for every 3 parts of hydrochloric acid, there is 1 part of nitric acid.

4. **Conclusion**: Therefore, aqua regia is a mixture of hydrochloric acid (HCl) and nitric acid (HNO3) in the ratio of 3:1.

5. **Final Answer**: The correct answer is that aqua regia is a mixture of hydrochloric acid (HCl) and nitric acid (HNO3).

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