when heated - calcium carbonate and carbon dioxide
when water is added-calcium hydroxide
used for - cement,mortar and concrete
Thermal decomposition -
calcium carbonatecalcium oxide + carbon dioxide
Metals high up in reactivity series - a lot of energy to decompose
Metals low down- easily decomposed colour change, from green copper carbonate to black copper oxide
Making calcium oxide + calcium hydroxide
--calcium carbonate calcium oxide + carbon dioxide
thermal decomposition reaction.
--Calcium oxide reacts with water to form calcium hydroxide, which is an alkali. Here are the equations for this reaction:
calcium oxide + water → calcium hydroxide
CaO + H2O → Ca(OH)2
A lot of heat is produced in the reaction, which may even cause the water to boil.
Uses of limestone
CaCO3 + 2HCl → CO2 + CaCl2 + H2O
limestone-damaged by acid ran (sulfur dioxide)
CO2 - detected using limewater
Cement, mortar, concrete
Cement is made by heating powdered limestone with clay. Cement is an ingredient in mortar and concrete:
- mortar, used to join bricks together, is made by mixing cement with sand and water
- concrete is made by mixing cement with sand, water and aggregate (crushed rock)
Limestone is a valuable natural resource, used to make things such as glass and concrete. Limestone quarrying provides employment opportunities that support the local economy in towns around the quarry. Limestone quarries are visible from long distances and may permanently disfigure the local environment.Quarrying is a heavy industry that creates noise and heavy traffic, which damages people's quality of life.