5) Acids and bases

Question 1

D) Arrhenious theory

Answer 1

Acids: produce H+ ions
Bases: produce OH- ions

Question 2

D) Lowry-bronsted theory

Answer 2

Acid: proton donor
Base: proton acceptor

Question 3

D) Lewis theory

Answer 3

Acid: contains vacant orbital
Base: contains lone pair

Question 4

D) Strong acids

Answer 4

Ionise completely.
HClO4
HCl
H2SO4
HNO3

Question 5

D) Strong bases

Answer 5

Dissociate completely,
NH2-
O2-
H-

Question 6

E) Molar expansion of water

Answer 6

Kw = [H3O+][OH-]
= 1 x 10-14

Question 7

E) pH and pOH

Answer 7

pH = -log [H+]
pOH = -log [OH-]
pH + pOH = 14

Question 8

E) % ionisation

Answer 8

= [H+] at equilibrium / [H+] initially x 100

Question 9

E) Ka and Kb

Answer 9

Ka = [H+][A-]/[HA]
Kb = [OH-][BH+]/[B]

Kw = Ka x Kb

Question 10

E) pH for buffers

Answer 10

pH = pKa + log( [conj base] / [acid])

Question 11

E) Salts

Answer 11

Salt = strong acid + strong base ion

Question 12

D) Buffers

Answer 12

Weak acid + its conj base
Weak base + its conj acid