Unit 3 Chapter 3: Equilibrium in acid base chemistry

Question 1

Bronsted-Lowry acid:

Answer 1

proton donor

Question 2

Bronsted-Lowry base:

Answer 2

proton acceptor

Question 3

Conjugate base:

Answer 3

formed by an acid when it donates a proton

Question 4

Conjugate acid:

Answer 4

formed by a base when it accepts a proton

Question 5

Conjugate acid-base pair:

Answer 5

molecules or ions that differ by a H+ ion

Question 6

Amphiprotic:

Answer 6

substance that can act as an acid or base

Question 7

Monoprotic:

Answer 7

can only donate one proton

Question 8

Polyprotic acid:

Answer 8

can donate more than one proton to a base
o First dissociation of a polyprotic acid occurs to a greater extent than those following. The extent decreases with each dissociation

Question 9

Properties of acids (out of 8):

Answer 9

• turns litmus indicator red
• corrosive
• sour
• react with bases
• low pH < 7
• donate H+
• dissociate to produce hydronium (H+)
• conduct electric current in solution

Question 10

Properties of bases (out of 8):

Answer 10

• turns litmus indicator blue
• caustic, slipper
• bitter
• react with acids
• high pH > 7
• accepts H+
• dissociate to produce hydroxide (OH-)
• conduct electric current in solution

Question 11

Concentrated acid/base:

Answer 11

contains more moles of solute per litre than a dilute acid/base

Question 12

Strong acid/strong bases:

Answer 12

more readily accept/receive protons than weaker acids/bases

Question 13

Stronger acid =

Answer 13

weaker conjugate base

Question 14

Stronger base =

Answer 14

weaker conjugate acid

Question 15

Strong acid examples (out of 2):

Answer 15

• Hydrochloric acid

- Sulfuric acid

Question 16

Weak acid examples (out of 2):

Answer 16

• Ethanoic acid

- Phosphoric acid

Question 17

Strong base examples (out of 2):

Answer 17

• Sodium hydroxide

- Potassium hydroxide

Question 18

Weak base example (out of 1):

Answer 18

• Ammonia

Question 19

Self-ionisation of water equation:

Answer 19

H2O + H2O <=> H3O+ + OH-

Question 20

Ionic product for water:

Answer 20

Kw = [H3O+][OH-] = 1.00 x 10^-14

Question 21

pH < 7:

Answer 21

acidic solution

Question 22

pH = 7:

Answer 22

neutral solution

Question 23

pH > 7:

Answer 23

basic (alkaline solution)

Question 24

Number of moles of acid/base in solution does not or does change during dilution?

Answer 24

Does not

Question 25

Acidic solution is diluted:

Answer 25

pH increases

Question 26

Basic solution is diluted:

Answer 26

pH decreases

Question 27

Buffer:

Answer 27

solutions that resist change in pH when a small amount of acid/ base is added

Question 28

Acidic Buffer solution:

Answer 28

formed by reacting weak acid, salt of the acid, and strong base

Question 29

Alkaline buffer solution:

Answer 29

formed by reacting weak base, salt of base, and strong acid

Question 30

Equilibrium expression for dissociation of monoprotic acid in water:

Answer 30

HA(aq) <=> H+(aq) + A-(aq)

Question 31

Equation for Ka=

Answer 31

Ka = [H+][A-]/[HA]

Question 32

Equation for Kb=

Answer 32

Kb = [NH4+][OH-]/[NH3]

Question 33

Acidity constant (Ka) measures:

Answer 33

strength of an acid

Question 34

Dissociation constant for base (Kb) measures:

Answer 34

strength of a base

Question 35

Indicator:

Answer 35

solutions of weak acid or base in solution with conjugate acid and base that change colour when pH = pKa

Question 36

Equivalence point:

Answer 36

point in titration when reactants have reacted in correct mole ratios

Question 37

End point:

Answer 37

point during titration where indicator changes colour