Acids, alkalis and salts

Question 1

Which type of ions do acids produce in aqueous solutions?

Answer 1

H⁺

Question 2

Acidic solutions have a pH of less than…

Answer 2

7

Question 3

Which type of ions do alkalis produce in aqueous solutions?

Answer 3

OH^-

Question 4

Alkalis have a pH value of more than…

Answer 4

7

Question 5

What is the pH value of a neutral substance?

Answer 5

7

Question 6

What is the colour of a strong acid in universal indicator?

Answer 6

Red

Question 7

What is the colour of a weak acid in universal indicator?

Answer 7

Orange - red

Question 8

What is the colour of a neutral solution in universal indicator?

Answer 8

Green

Question 9

What is the colour of a weak alkali in universal indicator?

Answer 9

Blue

Question 10

What is the colour of a strong alkali in universal indicator?

Answer 10

Purple

Question 11

Describe the colour of red litmus paper in acids, neutral solutions, and alkalis.

Answer 11

Red litmus paper:

• Stays red in acids
• Stays red in neutral solutions
• Turns blue in alkali solutions

Question 12

Describe the colour of blue litmus paper in acids, neutral solutions, and alkalis.

Answer 12

Blue litmus paper:

• Turns red in acids
• Stays blue in neutral solutions
• Stays blue in alkalis

Question 13

What is a base?

Answer 13

A substance that reacts with an acid to form salt and water

Question 14

What are the two types of bases?

Answer 14

• Metal oxides
• Metal hydroxides

Question 15

What are alkalis?

Answer 15

Bases that are soluble in water

Question 16

Which kinds of bases are alkalis (soluble in water)?

Answer 16

Metal hydroxides

Question 17

What is a neutralisation reaction?

Answer 17

A reaction between an acid and a base (to form a salt and water)

Question 18

Give the general word equation for a neutralisation reaction.

Answer 18

acid + base → salt + water

Question 19

Use an ionic equation to show how water is made in a neutralisation reaction.

Answer 19

H⁺ + OH^- → H₂O

Question 20

Give the general word equation for the reaction between a metal and an acid.

Answer 20

metal + acid → salt + hydrogen

Question 21

Which salt is made when iron reacts with sulfuric acid?

Answer 21

Iron sulfate

Question 22

magnesium + hydrochloric acid -→

Answer 22

magnesium chloride + hydrogen

Question 23

Sulfuric acid + copper oxide →

Answer 23

Copper sulfate + water

Question 24

Nitric acid + sodium hydroxide → sodium nitrate + water

Which type of reaction is this?

Answer 24

Neutralisation reaction

Question 25

What is the word equation for the reaction of an acid with a carbonate?

Answer 25

Acid + carbonate → salt + water + carbon dioxide

Question 26

Hydrochloric acid + copper carbonate →

Answer 26

copper chloride + water + carbon dioxide

Question 27

What is the formula of aluminium sulfate? The formulae of the ions are Al³⁺ and SO₄^2-

Answer 27

Al₂(SO₄)₃

Question 28

Copper sulfate can be made using a neutralisation reaction. What is this neutralisation reaction between?

Answer 28

copper oxide + sulfuric acid

Question 29

What is a dilute solution?

Answer 29

A solution that contains a relatively small amount of dissolved solute

Question 30

What is a concentrated solution?

Answer 30

A solution that contains a large amount of dissolve solute

Question 31

What are strong acids?

Answer 31

Acids that completely dissociate into H⁺ ions

Question 32

Hydrochloric acid is a strong acid. Which two ions does hydrochloric acid dissociate into?

Answer 32

Hydrogen (H⁺) and chlorine (Cl^-)

Question 33

What does the symbol ⇌ mean?

Answer 33

Reversible reaction