Acids and Bases Flashcards
Arrhenius Definition
Acid: a species that produces excess H+
Base: a species that produces excess OH-
Brønsted Lowry Definition
Acid: donates protons
Base: Accepts protons
Lews Definition
Acid: electron pair acceptor
Base: electron pair donor
pH+pOH=
pH + pOH = 14
Kw=
Kw = [H+][OH-] = 10^-14
pH=
pH = -log [H+] = log (1/[H+])
pOH=
pOH= -log [OH-] = log (1/[OH-])
Ka=
Ka = [H3O+][A-]/[HA]
Kb=
Kb = [B+][OH-]/[BOH]
Salt Formation
acids and bases may react with each other, forming a salt and water (usually) in a neutralization reaction, unless both weak
Hydrolysis
salt ions react with water to hive back the acid and base
Amphoteric Species
one that can act either as an acid or a base depending on its chemical environment
Titration
a procedure used to determine the molarity of an acid or a base by reacting a known volume of a solution of unknown concentration with a known volume of a solution of a known concentration
the half equivalence point defines pH=pKa
at colour change= endpoint
Henderson-Hasselbalch Equation Use
used to estimate the pH of a solution in the buffer region where the concentrations fo the species and its conjugate are present in approximately equal concentrations
Henderson-Hasselbalch Equation
pH = pKa + log [Conjugate Base]/[Weak Acid] pOH = pKb + log [Conjugate Acid]/[Weak Base]
