Acids and Bases

Question 1

Bronsted lowry base

Answer 1

proton acceptor

Question 2

bronsted lowry acid

Answer 2

proton donor

Question 3

strong acid/base

Answer 3

completely dissociates into ions in aqueous solution

Question 4

weak acid/base

Answer 4

slightly dissociates into ions in aqueous solution

Question 5

examples of weak acids and bases

Answer 5

• WA: carboxylics
• WB: ammonia

Question 6

pH equation

Answer 6

pH = -log10 [H+]

Question 7

kW value at 25 degrees Celsius

Answer 7

1x10-14

Question 8

kW equation

Answer 8

kW = [H+] [OH-]
kW = [H+]^2

Question 9

Ka equation

Answer 9

Ka = ([H+] [A-])/[HA]
Ka = [H+]^2 / [HA]

Question 10

Which way does the dissociation constant for weak acid shift when acid is added

Answer 10

…

Question 11

Which way does the dissociation constant for weak acid shift when alkali is added

Answer 11

…

Question 12

pKa equation

Answer 12

pKa = -log10 Ka

Question 13

Indicators

Answer 13

• used to show endpoint in titrations
• weak acids themselves
• phenolphthalein, methyl orange

Question 14

pH range of methyl orange and colours

Answer 14

• 3.2 - 4.4
• red in acid
• yellow in base
• orange endpoint

Question 15

pH range of phenolphthalein

Answer 15

• 8.2 - 10.0
• colourless in acid
• pink in base
• pale pink endpoint

Question 16

Describe SASB graph

Answer 16

(1) 3 5 (8) 11 (13)

Question 17

Describe SAWB graph

Answer 17

(1) 3 (5) 8 (11) 13

Question 18

Describe WASB graph

Answer 18

1 (3) (5) 8 11 (13)
with nose at start

Question 19

can you use an indicator with WAWB graph?

Answer 19

NO, equivolence point isn’t clear

Question 20

what to do to acid/bas pH when diprotic

Answer 20

multiply by 2!!

Question 21

number of dp for pH values

Answer 21

2

Question 22

number of sf for concentrations

Answer 22

3

Question 23

what are buffers

Answer 23

solutions that resist changes in pH upon addition of acid or alkali

Question 24

describe an acidic buffer

Answer 24

weak acid + its sodium/potassium salt

Question 25

describe an alkali buffer

Answer 25

ammonia + ammonium chloride

Question 26

pH of solution of SASB salt hydrolysis e.g. NaCl

Answer 26

- neutral - [H+] = [OH-]

Question 27

pH of solution of SAWB salt hydrolysis e.g. NH4Cl

Answer 27

- acidic - [H+] > [OH-]

Question 28

pH of solution of WASB salt hydrolysis e.g. Ch3COONa

Answer 28

- alkaline - [OH-] > [H+]

Question 29

pH of solution of WAWB salt hydrolysis e.g. CH3COONH4

Answer 29

- approximately neutral