Acids and Bases

Question 1

What is Kw?

Answer 1

The ionic product of water

Question 2

What is the pH scale a measure of?

Answer 2

Hydrogen ion conc.

Question 3

Define a Bronsted-Lowry acid

Answer 3

A proton donor - they release H+ ions when they are mixed with water

Question 4

Define a Bronsted-Lowry base

Answer 4

Proton acceptors

Question 5

What are the three types of acid?

Answer 5

Monobasic, dibasic, tribasic

Question 6

What is a conjugate pair?

Answer 6

Acids and bases that are linked by the transfer of a proton

Question 7

What are the products of acid + metal?

Answer 7

Salt + Hydrogen

Question 8

What are the products of acid + carbonate?

Answer 8

Salt + Carbon dioxide + Water

Question 9

What are the products of acid + metal oxide?

Answer 9

Salt + Water

Question 10

What was the first acid-base theory?

Answer 10

Lavoisier - acids had to have oxygen in them

Question 11

What disproves Lavoisier’s theory?

Answer 11

Acids such as HCl and H2S do not contain oxygen

Question 12

What was Arrhenius’ acid-base theory?

Answer 12

Acids release protons, Bases release OH-

Question 13

How is the Bronsted-Lowry theory different from Arrhenius’ theory?

Answer 13

The Bronsted-Lowry theory explains that a base is a proton acceptor. It also explains conjugate pairs

Question 14

What is the equation for calculating pH using H+ conc.?

Answer 14

ph=-log(H+)
(H+) = 10^-pH

Question 15

How do you calculate conc. of an acid when it is strong and monobasic?

Answer 15

(H+) = (acid)

Question 16

How do you find the pH of a strong base?

Answer 16

Kw = (H+)(OH-)
pH=-log(H+)

Question 17

What is Ka?

Answer 17

Acid dissociation constant

Question 18

How do you work out Ka?

Answer 18

Ka= (H+)(A-) / (HA)start

Ka= (H+)^2 / (HA)

Question 19

How do you find the conc. of a weak acid?

Answer 19

Use the Ka equation to find conc of H+
Then use this to work out pH

Question 20

How do you calculate pKa?

Answer 20

pKa = -logKa

Ka = 10^-pka

Question 21

What is the purpose of a buffer?

Answer 21

Buffers minimise changes in pH when small amounts of acid or base are added

Question 22

What do acidic buffers include?

Answer 22

Weak acid and conjugate base

Question 23

What is the buffer system in blood called?

Answer 23

Carbon acid-hydrogen carbonate buffer system

Question 24

What are the reactions in the carbonic acid-hydrogen carbonate buffer system?

Answer 24

H2CO3 ⇌ H+ + HCO3-
H2CO3 ⇌ H2O + CO2

Question 25

What is the name of the equipment that measures pH?

Answer 25

pH meter/ probe