Brønsted–Lowry Acid–Base Equilibria in Aqueous Solution (Oxford AQA International A Level Chemistry)
Revision Note
Written by: Alexandra Brennan
Reviewed by: Stewart Hird
Brønsted–Lowry Acid & Bases
The Brønsted-Lowry Theory defines acids and bases in terms of proton transfer between chemical compounds
A Brønsted acid is a species that can donate a proton
For example, hydrogen chloride (HCl) is a Brønsted acid as it can lose a proton to form a hydrogen (H+) and chloride (Cl-) ion
HCl (aq) → H+ (aq) + Cl- (aq)
A Brønsted base is a species that can accept a proton
For example, a hydroxide (OH-) ion is a Brønsted base as it can accept a proton to form water
OH- (aq) + H+ (aq) → H2O (l)
The Brønsted-Lowry Base behaviour of water and ammonia
Acid-base equilibria
The Brønsted-Lowry Theory is not limited to aqueous solutions only and can also be applied to reactions that occur in the gas phase
A Brønsted-Lowry acid and base reaction
Examiner Tips and Tricks
An atom of hydrogen contains 1 proton, 1 electron and 0 neutrons.
When hydrogen loses an electron to become H+ only a proton remains, which is why a H+ ion is also called a proton
Last updated:
You've read 0 of your 5 free revision notes this week
Sign up now. It’s free!
Did this page help you?
