Leaving Cert Chemistry - pH, Indicators and Acids and Bases (definitions)

Brønsted-Lowry Base

A base is a proton acceptor

Arrhenius Base

A base is a substance that dissociates in water to produce OH- ions

Brønsted-Lowry Strong Base

A good proton acceptor

Brønsted-Lowry Strong Acid

A good proton donor

Brønsted-Lowry Weak Base

A poor proton acceptor

Brønsted-Lowry Weak Acid

A poor proton donor

Arrhenius Strong Acid

A substance that almost completely dissociates in water to produce H+ ions

Arrhenius Strong Base

A substance that dissociates almost completely in water to produce OH- ions

Arrhenius Weak Acid

A substance that only slightly dissociates in water to produce H+ ions

Arrhenius Weak Base

A substance that only slightly dissociates in water to produce OH- ions

Conjugate Acid-Base Pair

An acid and a base which only differ by one proton

Brønsted-Lowry Acid

An acid is a proton donor

Arrhenius Acid

An acid is a substance that dissociates in water to produce H+ ions

Conjugate Acid

Arises when a base accepts a proton

Conjugate Base

Arises when an acid donates a proton

Ionic Product of Water

Kw = [H+][OH-]

pH

Minus the log to the base 10 of the H+ concentration

Indicators

Substances that change colour according to the pH of the solution they are placed in

Range of Indicator

The pH interval over which there is a clear change of colour for that indicator

Neutralisation

The reaction between an acid and a base to produce a salt and water