Bronsted-Lowry acids and bases

Arrhenius model of an acid

dissociate and release H+ ions in aqueous solution

Arrhenius model of a base

dissociate and release OH- ions in aqueous solution

What is base?

A base neutralizes an acid to form a salt. It is insoluble — e.g

How does an alkali differ to a base?

An alkali is a soluble base. e.g sodium hydroxide (NaOH)

Bronsted-Lowry acid

a proton donor (HCl)

Bronsted Lowry base

a proton acceptor (Cl-)

Conjugate acid-base pair

A conjugate acid-base pair contains two species that can be interconverted by transfer of a proton.

Conjugate base

HCl(aq) —> H+(aq) + Cl-(aq)

HCl releases a proton to form Cl-

Cl- is the conjugate base of HCl —> the base formed after HCl has released/donated a proton.

HCl / Cl- are a conjugate acid/base pair.

Conjugate acid

OH-(aq) + H+(aq) —> H2O (l)

OH- accepts a proton to form H2O

H2O is the conjugate acid of OH- —> the acid formed after OH- has accepted a proton.

H2O / OH- are a conjugate acid/base pair.