A2: Acids and Bases

Question 1

state the meaning of the term “WEAK” as applied to carboxylic acids

Answer 1

ONLY slightly or partially dissociated

Question 2

state the meaning of the term “Brønsted–Lowry” acid

Answer 2

Proton DONER (like donner kebab)

Question 3

What is the pH range for a
• STRONG acid
• STRONG base

Answer 3

1 - 13

Question 4

What is the pH range for a
• WEAK acid
• WEAK base

Answer 4

5 - 9

Question 5

What is the pH range for a
• STRONG acid
• WEAK base

Answer 5

1 - 9

Question 6

What is the pH range for a
• WEAK acid
• STRONG base

Answer 6

5 - 13

Question 7

Define “Buffer”:

Answer 7

A buffer is a solution that RESISTS CHANGES in pH when SMALL 👶 amounts of Acid or Alkali are added

Question 8

Acidic BUFFERS are made from
• ____ ____
• ____

and usually have a pH of:

Answer 8

• a WEAK acid
• it’s salt

pH: less than 7⃣

Question 9

define “racemic mixture” (racemate)

Answer 9

EQUAL mixture of enantiomers

Question 10

What is a BUFFER also known as?

Answer 10

an Acidity Regulator

Question 11

A method by which the mixture of amino acids formed by hydrolysis of a protein can be separated?

Answer 11

Chromatography

Question 12

Suggest one operating condition in an incinerator that would minimise the formation of dioxins:

Answer 12

high temperature (over 800 oC)

Question 13

Define “Dynamic Equilibrium”

Answer 13

• Forward and backward reactions proceeding at equal rate

- Amount of reactants and products remain constant

Question 14

Define “Reaction Rate”

Answer 14

CHANGE in the AMOUNT 🗻 of reactants OR products PER UNIT TIME ⏰

Question 15

If the rate constant is BIGGER…that means the reaction rate is…

Answer 15

FASTER

Question 16

If you ________ the TEMPERATURE, the rate KONSTANT _________ and the reaction RATE _________

(Why? 3 marks)

Answer 16

Increase, Increase, Increase

• inc temp = inc. the number of COLLISIONS 💨 between REACTANT molecules and also the ENERGY of each collision 💨. BUT, conc. of reactants and orders of reaction stay SAME so value of K must INCREASE for rate equation to balance

Question 17

WATER is _______ dissociated

Answer 17

WEAKLY

Question 18

The ____ ___________ step is the _______ step in a MULTI-STEP reaction:

Answer 18

• Rate-determining

- Slowest

Question 19

Define “Order of a reaction” (with respect to a reactant):

Answer 19

The order of a reaction, WITH RESPECT TO A REACTANT, shows the NUMBER OF MOLECULES of THAT reactant that are involved in the RATE-DETERMINING STEP