Reactions

Question 1

3 uses of oxygen:

Answer 1

Welding torches, rocket fuel, breathing apparatus in hospitals

Question 2

The word equation for respiration:

Answer 2

Sugar + oxygen -> carbon dioxide + water (energy)

Question 3

Describe the chemical test for water

Answer 3

Water turns white anhydrous copper sulfate blue

Question 4

Word equation for oxygen:

Answer 4

Hydrogen peroxide -> water + oxygen

Question 5

What is the catalyst in the preparation of oxygen?

Answer 5

Manganese dioxide

Question 6

What is the test for oxygen?

Answer 6

Glowing splint relights

Question 7

Give 2 examples of a catalyst (other than manganese dioxide)

Answer 7

Platinum, iron

Question 8

Word equation for hydrogen:

Answer 8

Magnesium + Hydrochloric acid -> magnesium chloride + hydrogen

Question 9

What is the test for hydrogen?

Answer 9

A squeaky pop

Question 10

What was Germany’s biggest airship called ?

Answer 10

The Hindenburg

Question 11

What could have caused the Hindenburg to explode into flames?

Answer 11

The outer skin was coated with waterproof paint which is flammable and it could have become charged with static electricity

Question 12

Word equation for carbon dioxide

Answer 12

Calcium carbonate + Hydrochloric acid -> calcium chloride + water + carbon dioxide

Question 13

What chemicals are required for the preparation of carbon dioxide?

Answer 13

Metal carbonate + acid

Question 14

3 uses for carbon dioxide

Answer 14

Fizzy drinks, fire extinguisher, dry ice

Question 15

2 observations when calcium is added to Hydrochloric acid

Answer 15

Bubbles of gas, lime water turns milky

Question 16

Definition of oxidation:

Answer 16

Addition of oxygen

Question 17

Definition of reduction:

Answer 17

Removal of oxygen

Question 18

What is a redox reaction?

Answer 18

Reduction and oxidation both taking place in a reaction

Question 19

Give 3 properties of oxygen:

Answer 19

Colourless, odourless and a gas

Question 20

What is an example of an endothermic reaction?

Answer 20

Sherbet dissolving on your tongue

Question 21

An example of an exothermic reaction:

Answer 21

Wood burning in fire

Question 22

What is thermal decomposition?

Answer 22

The breaking down of a chemical using heat energy

Question 23

What is an example of thermal decomposition?

Answer 23

Copper carbonate -> copper oxide -> carbon dioxide

Question 24

Thermite reaction equation:

Answer 24

Iron oxide + aluminium -> aluminium oxide + iron

Question 25

What is the equation for rusting?

Answer 25

Iron + oxygen + water -> hydrated iron oxide

Question 26

Word equation for burning fuel:

Answer 26

Fuel + oxygen -> carbon dioxide + water (+energy)