Topic 7: Acid, Bases & Salts

Question 1

How do acids react with metals?

Answer 1

Acids react with some metals to produce a salt and hydrogen gas

Question 2

Write the word and chemical equation of the reaction between magnesium and sulfuric acid.

Answer 2

magnesium + sulfuric acid —-> magnesium sulfate + hydrogen

Mg + H2SO4 —–> MgSO4 + H2

Question 3

Write the word and chemical equation of the reaction between iron and sulfuric acid.

Answer 3

iron + sulfuric acid —–> iron sulfate + hydrogen

Fe + H2SO4 ——-> FeSO4 + H2

Question 4

Name two types of bases.

Answer 4

Metal oxides
Alkalis

Question 5

How do bases react with acids?

Answer 5

When they react with acids, a neutralisation reaction occurs.

Question 6

Write the word and symbol equation for the reaction between sulfuric acid and potassium hydroxide.

Answer 6

sulfuric acid + potassium hydroxide —-> potassium sulfate + water

H2SO4 (aq) + 2KOH (aq) ——-> K2SO4 (aq) + 2H2O (l)

Question 7

Write the word ans symbol equation for the reaction between hydrogen bromide and magnesium hydroxide.

Answer 7

hydrogen bromide + magnesium hydroxide ——-> magnesium bromide + water

Mg(OH)2 (aq) + 2HBr (aq) ——–> MgBr2 (aq) + 2H2O (l)

Question 8

How do acids react with metal carbonates?

Answer 8

They react to from a salt, water and carbon dioxide.

Question 9

Write the word and symbol equation for the reaction between nitric acid and sodium carbonate.

Answer 9

Question 10

Write the word and symbol equation for the reaction between calcium carbonate and sulfuric acid.

Answer 10

Question 11

How do ammonium salts and alkalis react?

Answer 11

They react to produce salt, water and ammonia.
NaOH and KOH can be used as strong alkalis for this reaction to occur.

Question 12

Write the word and symbol equation for the reaction between ammonium chloride and sodium hydroxide.

Answer 12

Question 13

Tell me the colour of blue litmus in acids.

Answer 13

Red

Question 14

Tell me the colour of blue litmus in alkalis.

Answer 14

Blue

Question 15

Tell me the colour of methyl orange in acids.

Answer 15

Red

Question 16

Tell me the colour of methyl orange in alkalis.

Answer 16

Yellow

Question 17

Tell me the colour of thymolphthalein in acids.

Answer 17

colourless

Question 18

Tell me the colour of thymolphthalein in alkalis.

Answer 18

Blue

Question 19

Tell me the colour of phenolphthalein in acids.

Answer 19

Colourless

Question 20

Tell me the colour of phenolphthalein in alkalis

Answer 20

Pink

Question 21

Tell me the colour of red litmus in acids.

Answer 21

Red

Question 22

Tell me the colour of red litmus in alkalis

Answer 22

Blue

Question 23

Define base.

Answer 23

A substance that can react with acids and neutralise them

Question 24

Give examples of bases.

Answer 24

Metal oxides, metal hydroxides and metal carbonates

Question 25

Are bases soluble?

Answer 25

Many bases are insoluble but if a base does dissolve in water we call it an alkali

Question 26

Give examples of alkalis.

Answer 26

sodium hydroxide potassium hydroxide aqueous ammonia

Question 27

Tell me the difference between bases and alkalis.

Answer 27

Bases do not dissolve in water but bases that dissolve in water are alkali All bases are not alkali but all alkalis are bases Bases neutralise acids while alkalis release OH- ions (a proton acceptor)

Question 28

What happens when acids are in water?

Answer 28

They dissociate to form H+ ions.

Question 29

What are acids?

Answer 29

proton donors

Question 30

What are alkalis?

Answer 30

proton acceptors

Question 31

What are strong acids?

Answer 31

Acids that have a low ph (0-3) and fully dissociate into H+ ions in water

Question 32

Give examples of strong acids.

Answer 32

Hydrochloric acid Sulfuric acid Nitric acid

Question 33

What are weak acids.

Answer 33

Acids that have a higher pH (4-6) and partially dissociate into H+ ions in water

Question 34

Give examples of weak acids.

Answer 34

Ethanoic acid Citric acid Carbonic acid

Question 35

Are strong acids good conductors of electricity?

Answer 35

Yes

Question 36

Are weak acids poorer conductors of electricity?

Answer 36

Yes

Question 37

What is the pH a measure of?

Answer 37

the concentration of H+ ions in a solution

Question 38

What pHs do acids have?

Answer 38

A pH < 7

Question 39

What pHs do alkalis have?

Answer 39

a pH > 7

Question 40

What is a pH 7?

Answer 40

A neutral pH

Question 41

What are basic oxides?

Answer 41

Oxides that can neutralise an acid. Metals react with oxygen to form basic oxides

Question 42

Give examples of basic oxides.

Answer 42

Copper (II) oxide Iron (III) oxide Magnesium oxide

Question 43

What are acidic oxides.

Answer 43

Oxides that dissolve to form acids Non-metals react with oxygen to form acidic oxides

Question 44

Give examples of acidic oxides.

Answer 44

Carbon dioxide Sulfur dioxide Phosphorus pentoxide

Question 45

What are amphoteric oxides?

Answer 45

An oxide that reacts with both acids and alkalis

Question 46

Give examples of amphoteric oxides.

Answer 46

aluminium oxide zinc oxide

Question 47

Write the symbol equation for the reaction between sodium hydroxide and aluminium oxide.

Answer 47

Al2O3 + 6NaOH -----> 2Na3AlO3 + 3H2O

Question 48

What are neutral oxides?

Answer 48

Oxides that don't react with acids or bases

Question 49

Give examples of neutral oxides.

Answer 49

Carbon monoxide Dinitrogen oxide

Question 50

Tell me the solubility rules.

Answer 50

1. All nitrates are soluble in water 2. All chlorides, bromides and iodides are soluble in water, except those of lead and silver 3. All sulfates are soluble in water except barium, calcium and lead sulfates 4. All carbonates are insoluble, except those of potassium, ammonium and sodium 5. All hydroxides are insoluble, except sodium, potassium and ammonium and calcium (partially)