When two ice cubes are pressed over each other, they unite to form one cube. Which of the following forces is responsible to hold them together ?

Options

A. lonic interaction
B. Covalent attraction
C. van der Waals' forces
D. Hydrogen bond formation.

Explanation

To solve the question regarding the forces responsible for holding two ice cubes together when pressed, we can break it down into the following steps:

### Step-by-Step Solution:

1. **Understanding the Composition of Ice**:
- Ice is the solid form of water (H₂O). Each water molecule consists of two hydrogen atoms and one oxygen atom.

2. **Identifying the Interaction Between Ice Cubes**:
- When two ice cubes are pressed together, they come into contact with each other. The molecules at the surface of each ice cube interact with each other.

3. **Recognizing the Type of Bonding**:
- The primary force that holds the water molecules in ice together is hydrogen bonding. This occurs due to the polarity of the water molecule, where the oxygen atom is more electronegative than the hydrogen atoms.

4. **Formation of Hydrogen Bonds**:
- In ice, each water molecule can form hydrogen bonds with neighboring water molecules. When two ice cubes are pressed together, the hydrogen bonds can form between the hydrogen atoms of one ice cube and the oxygen atoms of the other ice cube.

5. **Conclusion**:
- The force responsible for holding the two ice cubes together is hydrogen bonding. This is the interaction that allows the ice cubes to unite and form a single larger cube.

### Final Answer:
The forces responsible for holding the two ice cubes together when pressed are **hydrogen bonds**.

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