Which of the following statements regarding boric acid is false?

Options

A. It acts as a weak monobasic acid
B. It is soluble in hot water
C. It has a planar structure
D. It acts as a tribasic acid

Explanation

To determine which statement regarding boric acid is false, let's analyze each statement one by one:

1. **Boric acid acts as a weak monobasic acid.**
- Boric acid (H3BO3) does indeed act as a weak monobasic acid. It does not donate protons (H⁺) in the same way that typical acids do; instead, it accepts a hydroxyl ion (OH⁻) from water, forming B(OH)4⁻. Therefore, this statement is **true**.

2. **Boric acid is soluble in hot water.**
- Boric acid is known to be soluble in hot water. When heated, it dissolves better than in cold water. Thus, this statement is also **true**.

3. **Boric acid has a planar structure.**
- The structure of boric acid is indeed planar, with the boron atom at the center and three hydroxyl (OH) groups arranged around it. This characteristic gives it a layered structure similar to graphite. Therefore, this statement is **true**.

4. **Boric acid acts as a tribasic acid.**
- This statement is false. Boric acid does not act as a tribasic acid because it does not donate three protons (H⁺) to form BO3³⁻. Instead, it behaves as a weak monobasic acid, accepting a hydroxyl ion rather than donating protons. Therefore, this statement is **false**.

### Conclusion:
The false statement regarding boric acid is that it acts as a tribasic acid.

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