If same mass of liquid water and a piece of ice is taken, then why is the density of ice less than that of liquied water ?

Explanation

To understand why the density of ice is less than that of liquid water when the same mass of both is taken, we can break down the explanation into several steps:

### Step-by-Step Solution:

1. **Definition of Density**:
- Density is defined as mass divided by volume (Density = Mass/Volume).

2. **Same Mass of Water and Ice**:
- We are considering equal masses of liquid water and ice. This means that the mass of both substances is the same.

3. **Structure of Ice**:
- Ice has a unique molecular structure. In ice, water molecules are arranged in a hexagonal lattice formation due to hydrogen bonding. This arrangement creates open spaces or "vacant spaces" between the molecules.

4. **Volume of Ice vs. Volume of Water**:
- The presence of these vacant spaces in the structure of ice means that for the same mass of water, ice occupies a larger volume compared to liquid water.

5. **Impact on Density**:
- Since density is inversely related to volume (for a constant mass), an increase in volume (as seen in ice) will lead to a decrease in density. Therefore, the density of ice is less than that of liquid water.

6. **Conclusion**:
- Thus, when comparing the same mass of ice and liquid water, ice has a greater volume due to its structure, resulting in a lower density.

### Final Statement:
The density of ice is less than that of liquid water because the structure of ice contains vacant spaces that increase its volume, leading to a lower density when the mass is constant.

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