Acids and Bases

Question 1

strong acid - [H+] =

Answer 1

10^-pH

Question 2

strong acid - -log(pH) =

Answer 2

[H+]

Question 3

define Bronsted-Lowry acid

Answer 3

proton donor

Question 4

define Bronsted-Lowry base

Answer 4

proton acceptor

Question 5

number of protons in a molecule of monoprotic acid

Answer 5

1

Question 6

number of protons in a molecule of diprotic acid

Answer 6

2

Question 7

equation of Kw in the ionic production of water

Answer 7

Kw = [H+][OH-] = Kc[H2O]

Question 8

Equation of Kc in the ionic production of water

Answer 8

Kc = [H+][OH-]/[H2O]

Question 9

the effect of temperature on the pH of water and why

Answer 9

as temperature increases, pH decreases (as more [H+])

Question 10

the effect of temperature on the ionic equilibrium of water

Answer 10

equilibrium moves to the right to oppose change

Question 11

equation for ionic production of water

Answer 11

H2O -> H+ + OH-

Question 12

is enthalpy change of the ionic product of water endo or exothermic

Answer 12

endothermic

Question 13

how can water have a lower pH but still be neutral?

Answer 13

because H+ increases but it still = OH-

Question 14

in pure water what does [OH-] =

Answer 14

[H+]

Question 15

in pure water, what does Kw =

Answer 15

[H+]^2

Question 16

in a strong base what does [H+] =

Answer 16

Kw/[OH-] or 10^-14/[OH-]

Question 17

steps in calculating pH of mixtures of strong acids and strong bases

Answer 17

calculate mols of H+ and OH-
calculate XS mols H+ or OH-
calculate conc. of XS H+ or OH-
calculate pH

Question 18

equation for a strong acid

Answer 18

HX -> H+ + X-

Question 19

equation for a weak acid

Answer 19

HX H+ + X-

Question 20

is HCl strong or weak

Answer 20

strong

Question 21

are carboxylic acids strong or weak

Answer 21

weak

Question 22

is sulphuric acid strong or weak

Answer 22

strong

Question 23

is nitric acid strong or weak

Answer 23

strong

Question 24

name a diprotic acid

Answer 24

sulphuric acid

Question 25

is barium hydroxide strong or weak

Answer 25

strong

Question 26

is potassium hydroxide strong or weak

Answer 26

strong

Question 27

is ammonia strong or weak

Answer 27

weak

Question 28

is sodium hydroxide strong or weak

Answer 28

strong

Question 29

name a dibasic base

Answer 29

barium hydroxide

Question 30

for a weak acid Ka =

Answer 30

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

Question 31

for a weak acid pKa =

Answer 31

-log Ka

Question 32

units for Ka

Answer 32

moldm^-3

Question 33

relationship between Ka and strength of acid

Answer 33

the bigger the value the stronger the acid

Question 34

relationship between pKa and strength of acid

Answer 34

the smaller the value the stronger the acid

Question 35

in a solution of a weak acid in water with nothing else added [H+] =

Answer 35

[A-]

Question 36

in a solution of a weak acid in water with nothing else added [HA] initial =`

Answer 36

[HA]

Question 37

in a solution of a weak acid in water with nothing else added Ka =`

Answer 37

[H+]^2/[HA]

Question 38

equation for reaction of a weak acid and a strong base

Answer 38

HA + OH- -> A- + H2O

Question 39

steps to finding the pH in reactions between weak acids and strong bases for XS HA

Answer 39

``` calculate mols HA calculate mols OH- calculate mols XS calculate mols HA left and A- formed use Ka to find [H+] find pH ```

Question 40

steps to finding the pH in reactions between weak acids and strong bases for XS OH-

Answer 40

``` calculate mols HA calculate mols OH- calculate mols XS calculate conc. OH- use Kw to find H+ find pH ```

Question 41

steps to finding the pH in reactions between weak acids and strong bases for when HA = OH-

Answer 41

calculate mols HA calculate mols OH- calculate mols XS pH = pKa of weak acid

Question 42

2H+ +CO3 2- ->

Answer 42

H2O + CO2

Question 43

H+ + HCO3- ->

Answer 43

H2O + CO2

Question 44

H+ + NH3 ->

Answer 44

NH4+

Question 45

define equivalence point

Answer 45

mols of alkali equals mols of acid present

Question 46

define buffer solutions

Answer 46

solution resists changes in pH when small amounts of acid or alkali are added

Question 47

what sort of buffer solutions have pH > 7

Answer 47

basic buffer solutions

Question 48

what sort of buffer solutions have pH < 7

Answer 48

acidic buffer solutions

Question 49

component in acidic buffer solution

Answer 49

weak acid + one of its salts

Question 50

component of basic buffer solution

Answer 50

weak base and one of its salts

Question 51

which equation can you use to find pH of acidic buffer solutions

Answer 51

Ka = [HA]/[A-]