Limestone

Question 1

What does limestone mainly consist of?

Answer 1

Calcium carbonate - CaCO3

Question 2

How is limestone removed from the ground?

Answer 2

Quarried

Question 3

What happens when limestone is heated?

Answer 3

It thermally decomposes to make calcium oxide and carbon dioxide

Question 4

What is the chemical formula for the reaction where limestone is heated?

Answer 4

CaCO3 - CaO + CO2

Question 5

What other carbonates decompose in the same way?

Answer 5

Magnesium
Copper
Zinc
Sodium

Question 6

Why might it be difficult to do these reactions at school?

Answer 6

Because a bunsen burner can’t reach a high enough temperature to thermally decompose some carbonates in Group 1 metals

Question 7

What are the main uses of limestone?

Answer 7

Building
Glass
Used to make cement

Question 8

What does calcium oxide reacting with water produce?

Answer 8

Calcium hydroxide

Question 9

What can calcium hydroxide be used for?

Answer 9

Neutralise acidic soil in fields. Powdered limestone can be used for this job too but calcium hydroxide works much faster.

Question 10

Calcium hydroxide (limewater) can be used as a test for which gas?

Answer 10

Carbon dioxide

Question 11

What happens to limewater if carbon dioxide is present?

Answer 11

It will turn from clear to cloudy . The cloudiness is caused by the formation of calcium carbonate.

Question 12

How do you make cement?

Answer 12

Powdered limestone is heated in a kiln with powdered clay to make cement

Question 13

How do you make mortar?

Answer 13

Cement can be mixed with sand and water to make mortar (calcium hydroxide can also be added)

Question 14

What is mortar?

Answer 14

Mortar is the stuff you stick bricks together with.

Question 15

How do you make concrete?

Answer 15

Mix sand and aggregate (water and gravel).

Question 16

What are some environmental problems of quarrying limestone?

Answer 16

1) It creates huge, ugly holes which permanently change the landscape
2) Quarrying processes , like balsting rocks apart with explosives, make lots of noise and dust in quiet, scenic areas = noise and dust pollution
3) Quarrying destroys the habitats of animals and birds
4) The limestone needs to be transported away from the quarry - usually in lorries. This causes more noise and pollution
5) Waste materials produce unsightly tips