Topic 7: Acids, Bases and Salts

Question 1

What do acids produce in water?

Answer 1

Hydrogen ions (H⁺).

Question 2

What is the definition of an acid?

Answer 2

Proton donor.

Question 3

What are the reactions of acids with metals?

Answer 3

Acid + Metal → Salt + Hydrogen gas.

Question 4

What are the reactions of acids with bases?

Answer 4

Acid + Base → Salt + Water.

Question 5

What are the reactions of acids with carbonates?

Answer 5

Acid + Carbonate → Salt + Carbon dioxide + Water.

Question 6

What color does blue litmus turn in acid?

Answer 6

Red.

Question 7

What color does methyl orange turn in acid?

Answer 7

Red.

Question 8

What is a base?

Answer 8

Substance that neutralizes acid to form salt and water.

Question 9

What is the definition of a base?

Answer 9

Proton acceptor (produces OH⁻ ions).

Question 10

What color does red litmus turn in a base?

Answer 10

Blue.

Question 11

What color does methyl orange turn in a base?

Answer 11

Yellow.

Question 12

What is an alkali?

Answer 12

A soluble base.

Question 13

pH range for acids?

Answer 13

1–6.

Question 14

pH of a neutral substance?

Answer 14

7.

Question 15

pH range for bases (alkalis)?

Answer 15

8–14.

Question 16

What does the pH scale measure?

Answer 16

Concentration of H⁺ ions.

Question 17

What does Universal Indicator show?

Answer 17

Colour linked to pH value.

Question 18

Describe neutralisation.

Answer 18

Acid + Alkali → Salt + Water.

Question 19

What is a strong acid?

Answer 19

Completely dissociates in water.

Question 20

What is a weak acid?

Answer 20

Partially dissociates in water.

Question 21

Example of a strong acid?

Answer 21

Hydrochloric acid (HCl).

Question 22

Example of a weak acid?

Answer 22

Ethanoic acid (CH₃COOH).

Question 23

What is a strong alkali?

Answer 23

Completely dissociates to form OH⁻ ions.

Question 24

Example of a strong alkali?

Answer 24

Sodium hydroxide (NaOH).

Question 25

What is a weak alkali?

Answer 25

Partially dissociates to form OH⁻ ions.

Question 26

Example of a weak alkali?

Answer 26

Ammonium hydroxide (NH₄OH).

Question 27

What are basic oxides?

Answer 27

Metal oxides like CuO and CaO.

Question 28

What are acidic oxides?

Answer 28

Non-metal oxides like CO₂ and SO₂.

Question 29

What are amphoteric oxides?

Answer 29

React with both acids and bases.

Question 30

Examples of amphoteric oxides?

Answer 30

Aluminium oxide (Al₂O₃) and Zinc oxide (ZnO).

Question 31

What are neutral oxides?

Answer 31

Do not react with acids or bases.

Question 32

Examples of neutral oxides?

Answer 32

Nitrous oxide (NO) and carbon monoxide (CO).

Question 33

What is a hydrated substance?

Answer 33

Substance combined with water.

Question 34

What is an anhydrous substance?

Answer 34

Contains no water.

Question 35

How to make soluble salts using an insoluble base?

Answer 35

React acid + excess base → Filter → Crystallise.

Question 36

How to make soluble salts using titration?

Answer 36

Neutralise acid and alkali → Crystallise.

Question 37

How to make insoluble salts?

Answer 37

Precipitation: mix two soluble salts → Filter precipitate.

Question 38

Colour of Copper (II) sulfate?

Answer 38

Blue.

Question 39

Colour of Copper (II) oxide?

Answer 39

Black.

Question 40

Colour of Copper (II) carbonate?

Answer 40

Green.

Question 41

Colour of Manganese (IV) oxide?

Answer 41

Black.

Question 42

Colour of Iron (II) salts?

Answer 42

Pale green.

Question 43

Colour of Iron (III) salts?

Answer 43

Brown or orange.

Question 44

What acid makes sulfate salts?

Answer 44

Sulfuric acid.

Question 45

What acid makes nitrate salts?

Answer 45

: Nitric acid.

Question 46

What acid makes chloride salts?

Answer 46

Hydrochloric acid.

Question 47

What acid makes ethanoate salts?

Answer 47

Ethanoic acid.

Question 48

Are all nitrates soluble?

Answer 48

: Yes.

Question 49

Are all sodium, potassium, ammonium salts soluble?

Answer 49

Yes.

Question 50

Which chlorides are insoluble?

Answer 50

Silver chloride and lead chloride.

Question 51

Which sulfates are insoluble

Answer 51

Barium sulfate, lead sulfate, calcium sulfate.

Question 52

Are most hydroxides soluble?

Answer 52

No, only sodium, potassium, ammonium (partially calcium).