Acid alkalis and making salts

Question 1

What happens to metal atoms when they react with other substances?

Answer 1

They form positive ions.

Question 2

What does the reactivity of a metal relate to?

Answer 2

Its tendency to form positive ions.

Question 3

What are redox reactions?

Answer 3

Reactions where one substance is oxidised and another is reduced.

Question 4

What does oxidation mean in terms of electrons?

Answer 4

Loss of electrons.

Question 5

What does reduction mean in terms of electrons?

Answer 5

Gain of electrons.

Question 6

What is the mnemonic for remembering oxidation and reduction?

Answer 6

OILRIG (Oxidation Is Loss, Reduction Is Gain).

Question 7

What do acids donate in solution?

Answer 7

H⁺ ions.

Question 8

List some common acids.

Question 9

What is the formula for sulphuric acid?

Answer 9

H₂SO₄.

Question 10

What is the formula for hydrochloric acid?

Answer 10

HCl.

Question 11

What is the formula for nitric acid?

Answer 11

HNO₃.

Question 12

What do bases donate in solution?

Answer 12

OH⁻ ions.

Question 13

What are alkalis?

Answer 13

Soluble bases.

Question 14

List some common alkalis.

Question 15

What is the formula for sodium hydroxide?

Answer 15

NaOH.

Question 16

What is the formula for potassium hydroxide?

Answer 16

KOH.

Question 17

What is the formula for calcium hydroxide?

Answer 17

Ca(OH)₂.

Question 18

What is the formula for ammonia?

Answer 18

NH₃.

Question 19

What are some common bases that do not dissolve in water?

Answer 19

Metal hydroxides, metal oxides, metal carbonates.

Question 20

What is the general reaction of a metal with an acid?

Answer 20

Metal + Acid → Salt + Hydrogen.

Question 21

What type of reaction occurs when a metal reacts with an acid?

Answer 21

Redox reaction.

Question 22

What do hydrochloric acid, sulphuric acid, and nitric acid produce?

Answer 22

Chlorides, sulphates, and nitrates respectively.

Question 23

What gas is produced during the reaction of a metal with an acid?

Answer 23

Hydrogen gas.

Question 24

What is produced during the neutralisation of an acid with an alkali/base?

Answer 24

Salt + Water.

Question 25

What is the general reaction of an acid with a carbonate?

Answer 25

Acid + Carbonate → Salt + Water + Carbon dioxide.

Question 26

What is an example of a reaction that produces effervescence?

Answer 26

Acid + Carbonate reaction.

Question 27

What is neutralisation?

Answer 27

When acids react with bases or alkalis to make a salt and water. The resulting solution has a neutral pH.

Question 28

What does an acid do during neutralisation?

Answer 28

Donates H+ ion to the base.

Question 29

What does a base do during neutralisation?

Answer 29

Accepts the proton.

Question 30

What is the ionic equation for neutralisation?

Answer 30

H+ (aq) + OH- (aq) → H2O (l)

Question 31

What are spectator ions?

Answer 31

Ions that do not change or react in the ionic equation.

Question 32

What is the first step in making a soluble salt?

Answer 32

Use a measuring cylinder to measure 30cm of relevant acid into a beaker.

Question 33

What should you do after measuring acid in the beaker?

Answer 33

Warm gently using a Bunsen burner placing it on a tripod and gauze.

Question 34

What is added to the acid during the salt-making process?

Answer 34

Half a spatula of relevant solid.

Question 35

What indicates that the solid is in excess during the salt-making process?

Answer 35

No more solid dissolves.

Question 36

What is the next step after allowing the mixture to cool?

Answer 36

Filter the mixture and discard the residue (excess solid).

Question 37

How do you obtain dry crystals from the filtrate?

Answer 37

Gently heat in a water bath until the volume has halved, then allow to crystallise.

Question 38

What are the three states of an indicator?

Answer 38

Acid, Neutral, Alkali.

Question 39

What color does Phenolphthalein turn in an alkali?

Answer 39

Pink.

Question 40

What color does Methyl orange turn in a neutral solution?

Answer 40

Yellow.

Question 41

What is the pH scale a measure of?

Answer 41

How acidic or alkaline something is and the concentration of hydrogen ions in a solution.

Question 42

What happens to pH as H+ concentration increases?

Answer 42

The pH decreases and the solution becomes more acidic.

Question 43

What tools can be used to measure pH?

Answer 43

pH meter/probe or universal indicator.

Question 44

Fill in the blank: Universal indicator color for pH 0-3 is _______.

Answer 44

red

Question 45

Fill in the blank: Universal indicator color for pH 7 is _______.

Answer 45

green

Question 46

Fill in the blank: Universal indicator color for pH 8-9 is _______.

Answer 46

blue