acids and bases

Arrhenius acid

dissociates to form an excess of H+ in solution

Arrhenius base

dissociate to form an excess of OH- in solution

Bronsted-lowry acid

donates H+ ions

bronsted-lowry base

species that accepts H+ ions

lewis acid

electron pair acceptor

lewis base

electron pair donor

amphoteric

behaves like an acid or a base

water dissociation constant (K_w)

[H30+][OH-] = 10^-14 @ 25^oC

pH and pOH

pH = -log[H+]

pOH = -log[OH-]

---

pH + pOH = 14

pH scale

acid = 0 < x < 7

base = 7 < x < 14

estimating pH or pOH value

n x 10^-m

---

p value = m - 0.n

strong acids and strong bases

strong acid

• HCl

• HBr

• HI

• H₂SO₄

• HNO₃

• HCLO₄

---

strong bases

• NaoH

• KOH

• other soluble hydroxides of Group IA metals

acid dissociation constant (K_a) and base dissociation constant (K_b)

K_a = [H30+][A-] / [HA]

K_b = [B+\[OH-] / [BOH]

titration

procedure used to determine the concentration of a known reactant in a solution

equivalence points on a titration curve

strong acid + weak base = EP pH < 7

strong acid + strong base = EP pH = 7

weak acid + strong base = EP pH > 7

buffer

mixture of weak acid and its salt (which is composed of its conjugate base and a cation) or a mixture of a weak base and its salt (which is composed of its conjugate acid and an anion)

---

resist pH change

Henderson-Hasselbalch equation

pH = pK_A + log( [A-] / [HA] )

pOH = pK_B + log( [B+] / [BOH] )