C1.2 Limestone and Building Materials Flashcards
How is limestone extracted?
It is quarried out of the ground
What compound is limestone mainly composed of?
Calcium carbonate - CaCO3
What products does the thermal decomposition of calcium carbonate (limestone) produce and what are their formulas?
Calcium oxide (CaO) Carbon dioxide (CO2)
Give four examples of carbonates that decompose in the same way as calcium carbonate.
- Sodium
- Zinc
- Copper
- Magnesium
Why would be virtually impossible to thermally decompose group 1 metal carbonates in a school class?
A bunsen burner can’t reach a high enough temperature to decompose them
What product does the reaction of calcium oxide with water produce and what is its formula?
Calcium hydroxide
Ca(OH)2
What is one use of calcium hydroxide and what is the property making this useful?
- It is used to neutralise acidic soil in fields as it is an alkali.
Describe how calcium hydroxide is used as a test for carbon dioxide and give the resulting equation.
- If you make a solution of calcium hydroxide in water (limewater) and bubble gas through it, it will turn cloudy if it contains carbon dioxide, caused by the formation of calcium carbonate.
calcium hydroxide + carbon dioxide ===> calcium carbonate
Give the three equations of the limestone cycle.
calcium carbonate ===> calcium oxide + carbon dioxide
calcium oxide + water ====> calcium hydroxide
calcium hydroxide + carbon dioxide ===> calcium carbonate + water
How is limestone used to make cement?
Powdered limestone and clay is heated in a hot kiln to make cement
How is mortar made and what is it used for?
It is made by mixing cement with sand and water to stick bricks together with
How is concrete made?
By mixing cement, sand and aggregate (water and gravel)
What is glass a mixture of?
- Limestone
- Sand
- Soda
How do carbonates react with acid?
To produce a salt, carbon dioxide and water
i.e
x carbonate + y acid ===> x y salt + carbon dioxide and water
How does calcium carbonate react with sulfuric acid?
calcium carbonate + sulfuric acid ===> calcium sulfate + carbon dioxide + water
What are the advantages of quarrying limestone?
- Limestone provides useful products
- Limestone products are used to neutralise acidic soil and acidity in lakes and river caused by acid rain
- Limestone can be used to neutralise sulfur dioxide in power station chimneys
- It provides jobs for people and brings more money into the local economy leading to improvements in roads, health etc
- Once it is complete, landscaping and restoration of the land is required
What are useful products made from limestone (6)?
- Houses
- Roads
- Paints
- Dyes
- Paints
- Machines
What are the disadvantages of quarrying limestone?
- Permanently damages the landscape
- Creates noise
- Creates dust which can cause breathing problems
- Energy is needed for the process = more fossil fuels
- Destroys animal habitats
- Transportation causes more pollution
- Waste materials cause tips
What are the advantages of using limestone and its products?
- Widely available and cheaper than granite or marble
- More hard wearing than marble
- Concrete can be poured into moulds to make blocks - a quick and cheap way of constructing buildings
- They don’t rot when wet
- Fire-resistant
- Concrete doesn’t corrode like metals
What are the disadvantages of using limestone and its products?
- Concrete is unattractive
- Concrete has a low tensile strength (cracks easily)
What damages limestone?
Acid rain
