Limestone

Question 1

Limestone reactions

Answer 1

1: limestone to quicklime
- Thermal decomposition
- Heated, will glow
- CaCO3 –> CaO + CO2
2: quicklime to slaked lime
- Absorbs small amount of water
- Hissing from Exothermic reaction
- Crumbles to powder calcium hydroxide
- CaO + H2O –> Ca(OH)2
3: temporary hard water
- CaCO3 + H2O + CO2 –> Ca(HCO3)2

Question 2

Uses of limestone

Answer 2

• Construction industry = cement to make mortar and concrete
• Make glass
• React with impurities in blast furnace from iron ore
• Slag used in road building
• Quicklime and slaked lime reduce acidity in soil
• Remove harmful gases in power stations
• Quarrying creates jobs and cheaper to quarry than other rocks

Question 3

Problems with quarrying

Answer 3

• Noise/Traffic pollution
• Habitats destroyed
• Dust
• Disfigures landscapes

Question 4

Reasons for quarrying limestone

Answer 4

• Useful in construction (roads and buildings)
• Construction materials e.g. glass, cement, concrete, mortar
• Jobs
• Benefit local economy
• Needed for extraction of iron

Question 5

Test for limewater

Answer 5

Bubble carbon dioxide through the water. Will go cloudy