Liquid water is denser than ice due to

Options

A. higher surface tension
B. hydrogen bonding
C. van der Waals forces
D. covalent bonding.

Explanation

To understand why liquid water is denser than ice, we can break down the explanation into several steps:

### Step-by-Step Solution:

1. **Understanding Density**:
- Density is defined as mass per unit volume. A substance is denser than another if it has more mass in the same volume.

2. **Behavior of Water**:
- Water (H₂O) exhibits unique properties due to hydrogen bonding. It is important to note that water reaches its maximum density at 4 degrees Celsius.

3. **Structure of Ice**:
- Ice forms a crystalline structure where water molecules are arranged in a cage-like formation. This structure is maintained by hydrogen bonds, which create a significant amount of open space between the molecules.

4. **Liquid Water Structure**:
- In contrast, when water is in its liquid state, the molecules are closer together. The hydrogen bonds in liquid water are constantly breaking and reforming, allowing the molecules to pack more closely together compared to ice.

5. **Comparison of Densities**:
- Since ice has a more open structure with more space between molecules, it is less dense than liquid water, which has a more compact arrangement of molecules.

6. **Conclusion**:
- Therefore, the reason liquid water is denser than ice is due to the hydrogen bonding that leads to a more compact arrangement of molecules in the liquid state compared to the open, cage-like structure of ice.

### Final Answer:
Liquid water is denser than ice due to hydrogen bonding, which allows water molecules to be more closely packed in the liquid state than in the solid state (ice).

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