Oxygen, Hydrogen, Carbon Dioxide, REDOX and Exo/Endothermic

Question 1

Which percentage of air is oxygen gas?

Answer 1

21%

Question 2

Name three uses of oxygen gas.

Answer 2

Welding torches

Rocket fuel

Breathing apparatus

Question 3

Give the general word for combustion.

Answer 3

fuel + oxygen –> carbon dioxide + water + energy

Question 4

Give the word equation for respiration

Answer 4

glucose + oxygen –> carbon dioxide+ water + energy

Question 5

Give the word equation for rusting

Answer 5

iron + oxygen + water –> hydrated iron oxide

Question 6

Which chemicals are required to prepare oxygen gas?

Answer 6

Hydrogen peroxide and manganese dioxide

Question 7

Give the word equation for the decomposition of hydrogen peroxide to form oxygen gas.

Answer 7

Question 8

Label the apparatus A-F for the preparation of oxygen gas.

Answer 8

A - Side arm test tube

B - Delivery tube

C- Oxygen gas

D - Trough

E - Hydrogen peroxide + manganese dioxide

F -Clamp

Question 9

What is a catalyst?

Answer 9

A chemical which speeds up a chemical reaction without being used up itself.

Question 10

What is the name of the catalyst used in the preparation of oxygen gas?

Answer 10

Manganese dioxide

Question 11

Name another catalyst

Answer 11

Enzymes

Question 12

Give three uses of carbon dioxide gas

Answer 12

Fire extinguishers

Dry Ice

Fizzy Drinks

Question 13

Give the general word equation for the production of carbon dioxide gas.

Answer 13

metal carbonate + acid ⇒ salt + water + carbon dioxide

Question 14

Give a word equation for the chemicals used to make carbon dioxide gas

Answer 14

calcium carbonate + hydrochloric acid ⇒ calcium chloride + water + carbon dioxide

Question 15

Label the apparatus A-E for the preparation of carbon dioxide gas.

Answer 15

A - side arm test tube

B - bung

C - downward delivery tube

D - limewater

E - marble chips (calcium carbonate ) + acid

Question 16

What is the test for carbon dioxide gas?

Answer 16

Bubble through limewater, it turns cloudy.

Question 17

Give three uses of hydrogen gas

Answer 17

Rocket fuel

Clean fuel for cars

Margarine

Question 18

Label the apparatus A - F for the preparation of hydrogen gas

Answer 18

A - retort stand

B - bung

C - clamp

D - test tube

E - upward delivery tube

F - side arm test tube

Question 19

Give the general word equation for the preparation of hydrogen gas.

Answer 19

Metal + Acid ⇒Salt + Hydrogen

Question 20

Give the word equation for the chemicals used to make hydrogen gas.

Answer 20

magnesium + hydrochloric acid ⇒ magnesium chloride + hydrogen

Question 21

What is the test for hydrogen gas?

Answer 21

Lighted splint, squeaky pop!

Question 23

What does exothermic mean?

Answer 23

Gives out heat

Question 24

What does endothermic mean?

Answer 24

Takes in heat

Question 25

What does REDOX mean?

Answer 25

Reduction and Oxidation taking place in a chemical reaction

Question 26

In the following reaction which substance has been oxidised and which has been reduced

magnesium oxide + sodium ⇒ sodium oxide + magnesium

Answer 26

Magnesium oxide is reduced

Sodium is oxidised