The various different building materials, such as limestone and metals, is one of the topics looked at in GCSE Science. This is the first of seven quizzes on that subject and it looks in particular at calcium carbonate, commonly found in limestone and chalk.
Calcium carbonate is a really important chemical that is used in the manufacture of lots of everyday items. Luckily, there is plenty of it just lying around - it is the main chemical in chalk and limestone. It is used to make many objects that you see all the time and it is unlikely that you will ever go for one whole day of your life without coming across something that needs calcium carbonate for its manufacture.
[readmore]The name tells you its chemical composition - it contains calcium, carbon and oxygen. A lot of the calcium carbonate is made by shell-building organisms (such as corals) and plankton . After the organisms die, they sink to the seafloor. Over time, layers of shells and sediment are cemented together and turn to rock, storing carbon in stone for millions of years in the form of limestones and chalk. Some limestones are made by chemical reactions in the sea, when the conditions are just right.
Quarrying of both limestone and chalk is carried out on a large scale in Britain. Some of the limestone and chalk is used for building but a lot of it goes to the manufacture of cement. There are a lot of environmental issues with both the quarrying and the processing of limestone and chalk but without the calcium carbonate that it provides, our world would be an incredibly different place. Test your knowledge of the chemistry and uses of this versatile and important chemical ...
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You can find more about this topic by visiting BBC Bitesize - Atoms, elements and compounds - AQA
We know from its name that calcium carbonate contains calcium, carbon and oxygen, so we can rule out option 1. Limestone and chalk are mainly CaCO3
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When a chemical is heated on its own and breaks down to form new materials, it is always called 'thermal decomposition'
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This is the basis of the cement making process
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This is called 'limelight' and was once used to provide lighting for the stages in theatres, hence the expression 'being in the limelight'
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This process of adding water to calcium oxide is called 'slaking'
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Oxides of metals are usually bases. If a base dissolves in water, it forms an alkali
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An easy question, but, if we had said the solution was limewater, the question would have been just too easy
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Calcium carbonate reacts with the common laboratory acids. It neutralises the acid and gives off carbon dioxide
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Farmers use it to neutralise slightly acidic soil
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The catch here was to include sand and aggregate. Often in everyday life, people talk about cement when they really mean mortar (sand and cement) or concrete (sand, cement and aggregate)
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