C1.2 Limestone and building materials

Question 1

What is limestone used as?

Answer 1

a building material

Question 2

What happens when calcium carbonate is decomposed by heating?

Answer 2

calcium oxide and carbondioxide are made

Question 3

What is the reaction called when limestone is heated to form calcium oxide and carbon dioxide?

Answer 3

Thermal decomposition

Question 4

What other carbonates decompose on heating in a similar way to calcium carbonate?

Answer 4

carbonates of magnesium, copper, zinc and sodium

Question 5

What is limestone mainly composed of?

Answer 5

the compound calcium carbonate

CaCO3

Question 6

What is thermal decomposition?

Answer 6

When one substance chemically changes into at least 2 new substances when heated

Question 7

Why may it be difficult to thermally decompose some carbonates ?

Answer 7

As a bunsen burner can’t reach high enough temperatures to thermally decompose some carbonates.

Question 8

What is produced when calcium oxide reacts with water?

Answer 8

calcium hydroxide.

Question 9

What can calcium hydroxide be used to do and why?

Answer 9

It can be used to neutralise acids as it is an alkali.

eg - neutralise acidic soil

Question 10

What is limewater?

Answer 10

A solution of calcium hydroxide in water.

Question 11

When calcium hydroxide reacts with carbondioxide , what is produced?

Answer 11

calcium carbonate

Question 12

Describe the test for carbon dioxide

Answer 12

Limewater is used as a test for CO2. Carbon Dioxide turns limewater cloudy.

Question 13

When carbonates react with acid, what is produced?

Answer 13

carbon dioxide, a salt and water

Question 14

How is cement made?

Answer 14

limestone is heated with clay

Question 15

how is mortar made?

Answer 15

limestone is heated with clay to make cement. Cement is mixed with sand.

Question 16

How is concrete made?

Answer 16

limestone is heated with clay to make cement. Cement is mixed with sand and aggregate.

Question 17

What are some negative impacts of quarrying limestone?

Answer 17

creates noise and dust

destroys habitats

Waste materials produce unsightly tips

Question 18

What are some negative impacts of making things from limestone?

Answer 18

cement factories make a lot of dust- breathing difficulties

energy is needed to produce cement- using fossil fuels

Question 19

What are some positive impacts of quarrying limestone?

Answer 19

limestone provides things people want- homes

limestone products use to neutralise soil

quarrying provides jobs

Question 20

Why is limestone a good building material?

Answer 20

widely available

cheaper than granite or marble

quick and cheap to construct buildings with

does not rot like wood

fire resistant

does not corrode like some metals

Question 21

What does calcium oxide react with to produce calcium hydroxide?

Answer 21

water

Question 22

What does calcium hydroxide react with to produce calcium carbonate?

Answer 22

carbon dioxide

Question 23

Why are buildings made from limestone affected by the products from burning fossil fuels containing sulfur?

Answer 23

Because sulfur reacts with oxygen to produce sulfur dioxide

sulfur dioxide causes acid rain that reacts with and erodes limestone

Question 24

Calcium hydroxide + more water ————–

Answer 24

calcium hydroxide solution

Question 25

calcium hydroxide solution + carbon dioxide ————

Answer 25

calcium carbonate

Question 26

Calcium carbonate + heat ———-

Answer 26

calcium oxide

Question 27

calcium oxide + water ———–

Answer 27

calcium hydroxide

Question 28

suggest why concrete is stronger than mortar

Answer 28

as concrete contains aggregate

Question 29

Name the type of reaction that takes place when calcium carbonate is heated strongly

Answer 29

thermal decomposition

Question 30

When limestone was heated, suggest why the predicted amount of carbon dioxide was not obtained

Answer 30

• limestone was not pure- so less carbon dioxide was produced
• the temperature was not high enough so the limestone did not fully decompose