Meaning & use
conjugate acid
Last updated
Meaning
nouncountabletechnicalchemistry
The acid formed when a base accepts a proton (H⁺), as defined by the Brønsted–Lowry theory.
Grammar: Countable: a conjugate acid, conjugate acids.
Patterns
- the conjugate acid of a base
- conjugate acid-base pair
When ammonia accepts a proton, it becomes the conjugate acid ammonium (NH₄⁺).
The conjugate acid of water is the hydronium ion (H₃O⁺).
Every base has a conjugate acid.
Word forms
| plural | conjugate acids |
|---|
Common combinations
- conjugate acid-base pair
- HCl and Cl⁻ form a conjugate acid-base pair.
- the conjugate acid of
- The conjugate acid of hydroxide is water.
- strong conjugate acid
- A strong base has a weak conjugate acid.
Synonyms and how they differ
Opposites
Word family
- conjugate verb
- To combine or be combined, especially in chemistry.
- conjugation noun
- The process of joining or the state of being joined.
Commonly confused: conjugate acid or conjugate base?
conjugate acid vs conjugate base
A conjugate base is what remains after an acid gives up a proton; a conjugate acid is formed when a base gains a proton.
Practice
What is the conjugate acid of the base NH₃?
Choose one answer.
NH₃ accepts a proton (H⁺) to become NH₄⁺, its conjugate acid. NH₂⁻ is the conjugate base, OH⁻ is the conjugate base of water, and H₃O⁺ is the conjugate acid of water.
Make it your own
Write a sentence using “conjugate acid”, then check it and compare it with the examples above.