What is limestone often formed from?
What compound is limestone mainly made up of?
How do we get limestone?
We quarry it out of the ground
What is limestone great for making into?
Blocks for building with
What property of limestone made people use it when building structures?
It's quite STURDY
What is the chemical formula for calcium carbonate?
What does calcium carbonate make when it THERMALLY DECOMPOSES?
1. Calcium oxide 2. Carbon dioxide
What are the word and symbol equations of the decomposition of calcium carbonate?
Calcium carbonate -> calcium oxide + carbon dioxide
CaO3 (s) --------> CaO(s) + CO2 (g)
Define thermal decomposition
When one substance CHEMICALLY changes into at least 2 NEW substances when it is HEATED
Which other 4 carbonates decompose the same way as calcium carbonate? Give an example
magnesium carbonate->magnesium oxide+carbon dioxide
MgCO3 -------> MgO + CO2
(REMEMBER these are CARBONATES not just the elements)
Why might you have difficulty doing a thermal decomposition reaction in class with some of the Group 1 metal carbonates?
A Bunsen burner CAN'T reach a HIGH enough temperature to thermally decompose some CARBONATES of Group 1 metals
What are the 3 products when calcium carbonate reacts with an acid?
1. a calcium SALT (i.e. calcium chloride)
2. Carbon dioxide
Give the word and symbol equations for calcium carbonate reacting with sulphuric acid
Calcium carbonate + sulphuric acid -> calcium sulphate + carbon dioxide + water
CaCO3 + H2SO4 -------> CaSO4 + CO2 + H2O
Which other 4 carbonates react with acids in the same way as calcium carbonate?
1. Copper 2. Zinc 3. Sodium 4. Magnesium
(HINT these are the same carbonates that thermally decompose in the same way as calcium carbonate)
What is the product when calcium oxide reacts with water?
What are the word and symbol equations for when calcium oxide reacts with water?
calcium oxide + water -------> calcium hydroxide
CaO + H2O -------> Ca(OH)2
What does the reaction between calcium carbonate and acid mean? (think buildings)
That limestone is damaged by acid rain
What 2 things can calcium hydroxide by used for, and why (for 1st one)?
1. For neutralising acidic soil in fields : It is an alkali
2. To test for carbon dioxide (in gas)
What is the advantage of using calcium hydroxide for neutralising soil in fields over powdered limestone?
Calcium hydroxide works much quicker than powdered limestone
What other substance, beside calcium hydroxide, can be used to neutralise acidic soil?
Explain step by step how a test for carbon dioxide in a gas using calcium hydroxide works?
1. You mix the calcium hydroxide with WATER to form a solution called LIMEWATER
2. Bubble GAS through it
3. The solution will turn CLOUDY if there's carbon dioxide in the gas
What causes the cloudiness in the limewater test?
The formation of CALCIUM CARBONATE
What are the word and symbol equations for the reaction that happens in limewater (calcium hydroxide)
Calcium hydroxide + carbon dioxide -> calcium carbonate + water
Ca(OH)2 + CO2 -------> CaCO3 + H20
What is the other name for calcium oxide?
Draw the 3 stages of the lime cycle
Draw and annotate the 4 stages and in-between bits of the lime cycle
What is the process where carbon gas is bubbled through calcium hyrdoxide (slakedlime) called?
The slakedlime is carbonated
How do you make cement out of powerdered limestone?
Heat the powered limestone in a kiln with powered clay
What 2 substances can be made out of mixing cement with things?
Cement can be mixed with ____ and ____ to make ____
Cement can be mixed with sand and water to make mortar
What is mortar useful for?
Sticking together bricks
What other substance can be added to mortar?
How do you make cement into concrete?
Mix the cement with sand and aggregate (water and gravel)
What is 'aggregate'?
Water and gravel
Name the 5 disadvantages of quarrying limestone
1. Scars the landscape
2. Quarrying process creates lots of noise and dust in quiet, scenic areas
3. Destroys habitats of birds and animals
4. Transportation of quarried limestone causes more noise and pollution
5. Waste materials produce unsightly tips
Name the 2 ways making things from limestone causes pollution, and the effects of them
1. Cement factories make a lot of dust, which can cause breathing problems for some people
2. Energy is need to produce cement and quicklime - will probably come from burning fossil fuels which causes pollution
Name the 4 good things limestone can be used for
1. Used in making houses, roads, chemicals used in dyes and paints in medicines
2. Neutralise acidic soil
3. Neutralise lakes and rivers made acidic by acid rain
4. Usind in power station chimneys to neutralise sulfur dioxide, which is a cause of acid rain
Name a human benefit of quarrying limestone
The quarry and associated business provide jobs for people and bring money into the local economy.
This can lead to local improvements in transport, roads, recreation facilities, and health.
Do quarrying firms just up and leave the local landscape in disarray?
Once quarrying is complete, restoration and landscaping is normally required as part of the planning permission
Name 10 advantages of using limestone products
1. Limestone, conctrete (made from cement) are sometimes perfect for the required type of building
2. Widely available
3. Cheaper than granite and marble
4. A fairly easy rock to cut
5. Some is more hard-wearing than marble, but still looks attractive
6. Concrete quickly and cheaply poured into moulds for construction
7. Limestone, concrete and cemement don't rot like wood does
8. Can't be gnawed away be insects or rodents
9. Fire resistant
10. Doesn't corrode
Name 3 disadvantages of using limestone products
1. In some case limestone and concrete (made from cement) can be a bit of a compromise when used in building
2. Concrete buildings are arguably ugly
3. Concrete has a low tensile strength and can crack
How can you make concrete buildings stronger?
By reinforcing them with steel bars