Success 24/7 Chemistry: 3 Theories of Acids and Bases
3 Theories (Definitions) of Acids and Bases
Arrhenius
• Acid: compound containing hydrogen that ionizes to yield hydrogen ions in solution
• Base: compound that ionizes to yield hydroxide ions in solution
Using the Arrhenius definition of acids and bases, label each of the following as either an acid or a base:
Ca(OH)2 ________
HNO3 __________
HC2H3O2 __________
KOH ___________
BrØnsted-Lowry
• Acid: hydrogen-ion donor (proton donor)
• Base: hydrogen-ion acceptor (proton acceptor)
• conjugate acid - particle formed when a base gains a hydrogen ion
• conjugate base - particle formed when an acid loses a hydrogen ion
HNO3 (l) + H2O(l) ↔ H3O+ (aq) + NO3 - (aq)
Practice:
Label the acid, base, conjugate acid, and conjugate base:
a. C2H5NH2 (l) + H2O(l) ↔ C2H5NH3 + (aq) + OH- (aq)
b. CH3CO2 H(l) + H2O(l) ↔ CH3CO2 - (aq) + H3O+(aq)
Write the formulas for the conjugate base of each of the following acids.
a. H2SO3 ___________
b. HCO3 - ___________
c. NH4 + ___________
Write the formulas for the conjugate acid of each of the following bases.
a. H2O
___________
b. CO3 2- ___________
c. PH3___________
•
amphoteric- substance that can act as both an acid and a base.
Ex. H2O, ZnO, Al(OH)3, Be(OH)2…
Lewis Acids and Bases
•
•
Acid: electron pair acceptor
Base: electron pair donor
NH3 + H+ → NH4+
Theory Name
Arrhenius
BrØnsted-Lowry
Lewis
Definition of Acid
Definition of Base