C9 Reactions of Acids

Question 1

In terms of pH what is an acid?

Answer 1

with a pH less than 7

Question 2

In terms of pH what is a neutral solution?

Answer 2

with a pH of 7

Question 3

In terms of pH what is an alkali?

Answer 3

with a pH above 7

Question 4

In terms of H+ ions what is an acid?

Answer 4

a substance that releases H+ ions when dissolved in water

Question 5

How is the amount of H+ ions in a solution related to the pH?

Answer 5

the more H+ ions, the lower pH

Question 6

How can you measure the pH of a substance?

Answer 6

litnus paper
universal indicator
pH probe

Question 7

What colour does blue litnus paper become with an acid?

Answer 7

Red

Question 8

What is a strong acid?

Answer 8

an acid where the molecules or ions completely ionise in water

Question 9

What is a weak acid?

Answer 9

an acid where the molecules or ions partially ionise in water

Question 10

What is a salt?

Answer 10

a compound formed when a metal ion takes the place of a hydrogen ion in an acid

Question 11

metal + acid –>

Answer 11

salt + hydrogen

Question 12

metal hydroxide + acid –>

Answer 12

salt + water

Question 13

metal oxide + acid –>

Answer 13

salt + water

Question 14

metal carbonate + acid –>

Answer 14

salt + water + carbon dioxide

Question 15

What is a base?

Answer 15

substance that reacts with acids in neutralisation reactions

Question 16

What is an alkali?

Answer 16

substance that dissolves in wate to form a solution above pH 7

Question 17

What is a neutralisation reaction?

Answer 17

a reaction between an acid and a base to produce WATER

Question 18

How can you obtain a solid salt from a solution?

Answer 18

crystallisation

Question 19

What is a redox reaction?

Answer 19

When one element does reduction and the other oxidises

Question 20

What is oxidation?

Answer 20

Loss of electrons

Question 21

What is reduction?

Answer 21

Gain of electrons