limestone and building materials Flashcards
What happens when calcium carbonate is heated (thermally decomposed)
breaks down to form calcium oxide and carbon dioxide
thermal decomposition
what happens when calcium oxide reacts with water
calcium hydroxide
what can limestone and its products be used for
make cement, mortar and concrete
what is limestone mainly
calcium carbonate
CaCO3
what is thermal decomposition
when something decomposes by heating strongly
what other metal carbonates thermally decompose similarly to calcium carbonate
sodium carbonate
magnesium carbonate
copper carbonate
zinc carbonate
do metals high in the reactivity series (sodium calcium and magnesium) need a lot of energy to decompose them or a little bit
a lot
not all carbonates of group 1 metals decompose at temperatures reached by a Bunsen burner
are metals low down in the reactivity series (copper) hard to decompose or easy
easy
why used at school
changes colour- green to black
easy to see
what is calcium hydroxide obtained from
calcium carbonate
how do u make calcium oxide
heat calcium carbonate strongly (thermal decomposition)
created calcium oxide and carbon dioxide
calcium oxide is yellow when hot but white when cold
how do you make calcium hydroxide
calcium oxide and water forms calcium hydroxide (it’s an alkali)
a lot of heat is produced in this reaction
what is limestone a type of
Rock, mainly composed of calcium carbonate
how is limestone obtained
CaCO3 is quarried and can be used as a building material
what do carbonate produce when they react with an acid
Carbon dioxide, a salt and a water
calcium carbonate + hydrochloric acid > carbon dioxide + calcium chloride + water
what damages limestone
acid rain
what carbonates react with acids
sodium carbonate
magnesium carbonate
zinc carbonate
copper carbonate
they all fizz and release carbon dioxide
how can you text for carbon dioxide
like water f turns cloudy
what is calcium hydroxide used for
to neutralise acidity ED lakes and soils affected by acid rain
what is cement
made by heating powdered limestone with clay
it is an ingredient in motar and concrete
what is motar
made by mixing cement with sand and water
used to join bricks together
what is concrete
made by mixing cement with sand, water and aggregate (crushed rock)
advantages of concrete
easily formed into different shapes
strong when squashed, weak when bent or stretched
disadvantages of concrete
made stronger by reinforcing it with steel
some say concrete building and bridges are unattractive
disadvantages with limestone cement and motar
react with carbon dioxide dissolved in rainwater and wear away- damages walls and leaves gaps
polliution makes rain more acidic making problems worse
