Mercury sinks in water due to its high _________.

Options

A. Weight
B. Velocity
C. Density
D. Reactivity

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:**
The question asks why mercury sinks in water. We need to identify the property of mercury that causes it to sink.

2. **Identifying the Options:**
The options given are:
A. It has weight.
B. It has velocity.
C. It has density.
D. It has reactivity.

3. **Analyzing Each Option:**
- **A. It has weight:** While mercury does have weight, weight alone does not determine whether an object sinks or floats.
- **B. It has velocity:** Velocity is related to the speed of an object and does not influence whether it sinks or floats.
- **C. It has density:** Density is a measure of how much mass is contained in a given volume. An object will sink in a fluid if its density is greater than that of the fluid.
- **D. It has reactivity:** Reactivity refers to how readily a substance undergoes a chemical reaction, which is not relevant to sinking or floating.

4. **Conclusion from Analysis:**
The correct option is **C. It has density.** Mercury sinks in water because its density is higher than that of water.

5. **Providing Density Values:**
- The density of mercury (Hg) is approximately **5.43 grams per cubic centimeter (g/cm³)**.
- The density of water (H₂O) is approximately **1 gram per cubic centimeter (g/cm³)**.

6. **Final Statement:**
Since the density of mercury is greater than that of water, mercury sinks in water.

**Final Answer:**
Mercury sinks in water due to its high **density**.

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