What do you mean by anomalous expansion of water?

Answer

**Step-by-Step Solution:**

1. **Definition of Anomalous Expansion of Water**: Anomalous expansion of water refers to the unique behavior of water when it is cooled, particularly between the temperatures of 4°C and 0°C.

2. **Behavior of Water**: Normally, substances expand when heated and contract when cooled. However, water behaves differently in the temperature range from 4°C to 0°C. As water cools down from 4°C to 0°C, it actually expands instead of contracting.

3. **Volume and Density Changes**: When water cools from 4°C to 0°C, its volume increases, leading to a decrease in density. This means that the density of water is highest at 4°C and decreases as it approaches 0°C.

4. **Implications of Anomalous Expansion**: This property of water has significant implications in nature, such as the freezing of lakes and ponds. Ice, which is less dense than liquid water, floats on the surface, insulating the water below and allowing aquatic life to survive in cold conditions.

5. **Conclusion**: In summary, the anomalous expansion of water is a unique characteristic that occurs when water is cooled from 4°C to 0°C, resulting in an increase in volume and a decrease in density.

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