Conjugate acid-base pairs are related substances that differ by a single proton (H⁺). Here’s a explanation:
1. Definition
- When an acid donates a proton, it forms its conjugate base.
- When a base accepts a proton, it forms its conjugate acid.
2. Examples
- HCl and Cl⁻
- HCl → Cl⁻ + H⁺
- HCl = acid, Cl⁻ = conjugate base
- NH₃ and NH₄⁺
- NH₃ + H⁺ → NH₄⁺
- NH₃ = base, NH₄⁺ = conjugate acid
3. Key Points
- Every acid has a conjugate base.
- Every base has a conjugate acid.
- They show the reversibility of acid-base reactions.
In short:
Conjugate acid-base pairs are two substances that transform into each other by gaining or losing one H⁺.