Properties of acidic solutions:
> Turn litmus red
> Neutralised by bases
> pH <7
> Liberate CO2 from carbonates
Acids = proton donors & Bases = proton acceptor = Bronsted-Lowry Theory
Solutions of Acids & Bases
HCl conducts electricity, so must contain ions
HCl + H2O --> H3O+ + Cl-
H3O+ Oxonium ion - present in every solution of an acid in water & can donate H+
When an acid dissolves in water, H+ ions form in solution.
Alkali = base that dissolves in water to produce OH ions
Conjugate base: eg ethanoate ions accept H+ ions from the stronger acid and go back to ethanoic acid
HA --> H+ + A-
Conjugate acid --> H+ + conjugate base
If water is reacting with a strong acid, water acts as a base
If water is reacting with a strong base - water acts as an acid
Water = amphoteric
Strength of Acids & Bases and Indicators
A strong acid has a weak conjugate base.
Strong acid: strong tendancy to donate H+ Conjugate base: weak tendancy to accept them back
Concentration - number of particles in a given volume of solution.
Coloured organic substances which are weak acids.
The conjugate acid and base have different colours.
Litmus acid: red conjugate base: blue