Which one of the following statements about water is FALSE ?

Options

A. Water can act both as an acid and as a base.
B. There is extensive intramolecular hydrogen bonding in the condensed phase.
C. Ice formed by heavy water sinks in normal water.
D. Water is oxidized to oxygen during photosynthesis.

Explanation

To determine which statement about water is false, we will analyze each of the four options provided.

### Step-by-Step Solution:

1. **Analyze Option 1:**
- Statement: "Water can act both as an acid and as a base."
- Explanation: Water is amphoteric, meaning it can act as both an acid and a base. It can donate a proton (H⁺) to become OH⁻ (hydroxide ion) and can accept a proton to become H₃O⁺ (hydronium ion).
- Conclusion: This statement is **true**.

2. **Analyze Option 2:**
- Statement: "There is extensive intramolecular hydrogen bonding in the condensed phase of water."
- Explanation: Intramolecular hydrogen bonding occurs within a single molecule, while water primarily exhibits intermolecular hydrogen bonding between different water molecules. In a water molecule (H₂O), the hydrogen atoms are bonded to the oxygen atom, and there is no significant intramolecular hydrogen bonding.
- Conclusion: This statement is **false**.

3. **Analyze Option 3:**
- Statement: "Ice formed by heavy water sinks in normal water."
- Explanation: Heavy water (D₂O) has a higher density than normal water (H₂O). Therefore, ice made from heavy water will sink in normal water due to its greater mass.
- Conclusion: This statement is **true**.

4. **Analyze Option 4:**
- Statement: "Water is oxidized to oxygen during photosynthesis."
- Explanation: During photosynthesis, water undergoes photolysis, where it is split into oxygen and hydrogen ions. The oxygen produced is indeed derived from the oxidation of water.
- Conclusion: This statement is **true**.

### Final Conclusion:
After analyzing all options, the false statement about water is **Option 2: "There is extensive intramolecular hydrogen bonding in the condensed phase of water."**

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