Mention the temperature at which density of ice is maximum.

Answer

To solve the question regarding the temperature at which the density of ice is maximum, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Density of Water and Ice**:
- The density of a substance is defined as its mass per unit volume. For water, the density changes with temperature.

2. **Identify the Maximum Density of Water**:
- Water reaches its maximum density at 4 degrees Celsius. At this temperature, water molecules are packed closely together, resulting in a higher density.

3. **Behavior of Water as it Freezes**:
- As water cools down to 0 degrees Celsius and begins to freeze, it forms ice. Ice has a crystalline structure that creates more empty space compared to liquid water.

4. **Density of Ice**:
- Ice is less dense than liquid water. This is why ice floats on water. The maximum density of ice occurs at temperatures above 0 degrees Celsius, but it is still less than that of liquid water at 4 degrees Celsius.

5. **Conclusion**:
- The maximum density of ice occurs at 0 degrees Celsius, but it is important to note that this density is lower than the maximum density of water at 4 degrees Celsius.

### Final Answer:
The temperature at which the density of ice is maximum is **0 degrees Celsius**.

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