Amphoteric

Definition

An amphoteric substance can act as both an acid and a base. This dual behavior depends on the chemical environment it encounters.

5 Must Know Facts For Your Next Test

1. Water is a common example of an amphoteric substance.
2. Amphoteric behavior is explained by the Brønsted-Lowry theory, where substances can either donate or accept protons.
3. Aluminum hydroxide (Al(OH)3) and zinc oxide (ZnO) are examples of amphoteric compounds.
4. Amphoteric substances can neutralize both acids and bases, forming salts and water in the process.
5. The pH at which an amphoteric molecule has no net charge is called its isoelectric point.

Review Questions

• What does it mean for a substance to be amphoteric?
• Give two examples of amphoteric substances besides water.
• How does Brønsted-Lowry theory explain the behavior of amphoteric substances?

Related terms

Brønsted-Lowry Acid: A substance that donates a proton (H\(^+\)) in a chemical reaction.

Brønsted-Lowry Base: A substance that accepts a proton (H\(^+\)) in a chemical reaction.

Isoelectric Point: The pH at which an amphoteric molecule has no net electrical charge.