Key Area 4: Acids and Bases

Question 1

The pH scale

Answer 1

runs from below 0 to above 14

Question 2

A neutral solution has

Answer 2

equal concentrations of H+ (aq) and OH - (aq) ions

Question 3

The symbol = with the arrows means

Answer 3

a reaction is reversable

Question 4

Bases

Answer 4

Alkalis (metal hydroxides)
metal oxides
metal carbonates

Question 5

All acids contain

Answer 5

hydrgoen ions H+

Question 6

All alkalis contain

Answer 6

Hydroxide ions OH-

Question 7

If you dilute an acid by a factor of 10

Answer 7

the pH goes up by 1

Question 8

If you dilute an alkali by a factor of 10

Answer 8

the pH goes down by 1

Question 9

Conducting liquids and solutions are called

Answer 9

Electrolytes (conducting liquid)

Question 10

The three stages of a method

Answer 10

Neutralisation
Filtration
Evaporation (crystallisation)

Question 11

Base equation

Answer 11

Base + Acid —> Salt + Water

Question 12

Carbonate equation

Answer 12

Acid + Metal carbonate –> Salt + Carbon Dioxie + water

Question 13

Carbonates of group 1 are soluble

Answer 13

therefore alkalis

Question 14

A good indicator will produce a

Answer 14

sudden sharp colour change

Question 15

Strong acids

Answer 15

pH less than 2

Question 16

weak acids

Answer 16

pH 3-6

Question 17

neutral

Answer 17

pH 7

Question 18

strong alkali

Answer 18

pH 12 and above

Question 19

pH can only be measured if?

Answer 19

water is present

Question 20

the exact point where neutralisation occurs?

Answer 20

end-point

Question 21

Acid

Answer 21

Anything with a pH less than 7

Question 22

Base

Answer 22

Neutralises acids, resulting in the pH of the acid increasing towards 7, and water being produced