Which of the following statements is incorrect?

Options

A. Gold and silver are the most malleable and ductile metals.
B. All metals are hard and strong.
C. Mercury and gallium are metals which exist in liquid state at room temperature.
D. Most of the metals have high specific gravities.

Explanation

To determine which statement is incorrect, we will analyze each of the four options provided in the question.

### Step-by-Step Solution:

1. **Analyze Option 1: "Gold and silver are most malleable and ductile metals."**
- **Explanation:** Malleability refers to the ability of a metal to be hammered or rolled into thin sheets, while ductility is the ability to be drawn into wires. Gold and silver are indeed known for their high malleability and ductility.
- **Conclusion:** This statement is **correct**.

2. **Analyze Option 2: "All metals are hard and strong."**
- **Explanation:** While many metals are hard and strong, this statement is too absolute. There are exceptions, such as sodium and potassium, which are soft metals that can be cut with a knife.
- **Conclusion:** This statement is **incorrect**.

3. **Analyze Option 3: "Mercury and gallium are metals which exist in liquid state at room temperature."**
- **Explanation:** Mercury is well-known for being a liquid metal at room temperature. Gallium can also exist in a liquid state just above room temperature.
- **Conclusion:** This statement is **correct**.

4. **Analyze Option 4: "Most of the metals have high specific gravities."**
- **Explanation:** Specific gravity is a measure of density. Most metals do indeed have high densities, which means they have high specific gravities.
- **Conclusion:** This statement is **correct**.

### Final Conclusion:
The incorrect statement among the options is **Option 2: "All metals are hard and strong."**

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