Acids & Bases, pH & Buffers

Question 1

What is an acid?

Answer 1

A substance that produces H+ ions in aqueous solution (Hydrogen ion donors)

Question 2

What are the original defining properties of an acid?

Answer 2

Sour taste, corrosive, conduct electricity (electrolytes) and turn litmus paper red

Question 3

What is the difference between strong acids and weak acids?

Answer 3

Strong acids ionise completely in water. (Strong acids contain lots of H+ ions)
Weak acids only partially ionise in water. (contains only a few H+ ions)

Question 4

Name a strong acid and a weak acid

Answer 4

Hydrochloric acid and carbonic acid

Question 5

A base ____ H+ ions from aqueous solutions and produces _____?

Answer 5

Removes, OH- ions.

Question 6

Bases ______ fats and ____?

Answer 6

Hydrolise, oils

Question 7

Bases are?

Answer 7

Proton acceptors. They remove H+ ions from solutions.

Question 8

Name some examples of bases

Answer 8

Ammonia, magnesium hydroxide

Question 9

_____ + _____ > Water + Salt. What is this called?

Answer 9

Acid + Base. A neutralisation reaction. The salt formed is an ionic compound

Question 10

pH less that 7 is _____, above 7 is _____ and pH of 7 is _____

Answer 10

Acidic, Alkaline (Basic), Neutral

Question 11

What is the normal pH of blood?

Answer 11

7.35 to 7.45

Question 12

What is used to keep a constant pH?

Answer 12

A buffer solution

Question 13

In which circumstance would a constant pH be needed?

Answer 13

Biological reactions or chemical processes in industry and research

Question 14

In blood if the pH of blood is too high it is called _______ (too much ___)

Answer 14

Alkalosis (too much OH-)

Question 15

In blood if the pH of blood is too low it is called _______ (too much ___)

Answer 15

Acidosis (too much H+)

Question 16

Describe the function of the carbonic acid/bicarbonate buffer in blood

Answer 16

Carbonic acid = weak acid
Bicarbonate = weak base.
Maintain pH by controlling amount of H+ ions

Question 17

If acid is added (more H+) the _______ reaction will increase, _____ the extra H+

Answer 17

Reverse, using up

Question 18

If base is added (H+ removed) the ______ reaction will ______ to _______ H+

Answer 18

Forward, replace