amphiprotic

Thân thiện

An amphiprotic substance can donate or accept a proton in a chemical reaction.

Definition

1. Adjective:
   • Having characteristics of both an acid and a base and capable of reacting as either: Describes a substance, typically a molecule or ion, that can either donate a proton (act as an acid) or accept a proton (act as a base) depending on the chemical environment.

Usage Examples

• Adjective:
  • Water is a classic example of an amphiprotic substance.
  • The amino acid glycine is amphiprotic, allowing it to function in various biochemical reactions.
  • In this reaction, the bicarbonate ion (HCO₃⁻) behaves in an amphiprotic manner.

Advanced Usage

• "Amphiprotic solvent": A solvent that can act as both a proton donor and a proton acceptor.
  • Amphiprotic solvents like water and ethanol are crucial for many acid-base reactions.
• "Amphiprotic species": A general term for any molecule or ion that exhibits amphiprotic behavior.
  • The dihydrogen phosphate ion (H₂PO₄⁻) is a common amphiprotic species in buffer solutions.

Variants and Related Words

• Amphoteric (adj): A broader term describing a substance that can react as both an acid and a base. While often used interchangeably with "amphiprotic," "amphoteric" can also refer to reactions not involving proton transfer (e.g., with metal oxides).
  • Aluminum hydroxide is amphoteric, dissolving in both acids and bases.
• Ampholyte (n): A molecule, especially an amino acid or protein, that possesses both acidic and basic groups and is therefore amphoteric/amphiprotic.
  • Proteins are ampholytes, which is exploited in techniques like isoelectric focusing.

Synonyms

• Amphoteric: Having the characteristics of both an acid and a base.
• Zwitterionic (in specific contexts, for molecules that carry both positive and negative charges at neutral pH, a consequence of amphiprotic behavior).

Related Phrases and Concepts

• Conjugate acid-base pair: A pair of two species that transform into each other by the gain or loss of a proton. Amphiprotic substances are central to such pairs.
  • In the pair H₂PO₄⁻/HPO₄²⁻, the dihydrogen phosphate ion is the amphiprotic member.
• Autoionization: A process where a substance reacts with itself. This is a key property of amphiprotic solvents like water (H₂O + H₂O ⇌ H₃O⁺ + OH⁻).

Học thuật

Adjective

1. having characteristics of both an acid and a base and capable of reacting as either

Từ đồng nghĩa

• amphoteric