Why is mercury placed below hydrogen in the metal reactivity serices?

Options

A. It has a high density.
B. It is more reactivity
C. It has more mass.
D. It is less reactive.

Answer

To answer the question of why mercury is placed below hydrogen in the metal reactivity series, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Reactivity Series**:
- The reactivity series is a list of metals arranged in order of decreasing reactivity. It helps in predicting how metals will react with other substances, including acids and water.

2. **Identifying the Position of Mercury and Hydrogen**:
- In the reactivity series, metals are listed from most reactive to least reactive. The series typically includes metals like sodium, calcium, magnesium, aluminum, zinc, iron, lead, hydrogen, copper, mercury, silver, and gold.

3. **Comparing Reactivity**:
- Reactivity refers to how readily a metal reacts with other substances. As we move down the reactivity series, the reactivity of metals decreases.

4. **Analyzing Mercury's Reactivity**:
- Mercury (Hg) is a metal that does not react vigorously with acids or water. Its reactivity is lower than that of hydrogen (H).

5. **Conclusion**:
- Since mercury is less reactive than hydrogen, it is placed below hydrogen in the reactivity series. This positioning indicates that mercury will not displace hydrogen from its compounds, which is a key factor in determining the order of metals in the series.

### Final Answer:
Mercury is placed below hydrogen in the metal reactivity series because its reactivity is less than that of hydrogen.

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