COMPOUND- a substance made of two or more types of atom chemically joined together
ELEMENT- a substance made of only one type of atom
MIXTURE- a combination of two or more elements in a way that allows each element to keep its own chemical identity.
All substances are made up of atoms
Elements contain only one type of atom
Different atoms can bond together by giving/taking/sharing electrons, to form compounds.
Atoms are made up of a tiny central nucleus surrounded by electrons 1.2 Limestone and its uses
airborne pollution = dust, gases, noise and vibration (machinery) and during blasting in quarries, and damage to countryside from quarrying
Limestone is made mainly of calcium carbonate (CaCo3)
Some types of limestone are made of the remains of tiny animals and plants which lived in the sea millions of years ago
We dig limestone out of the ground in quarries
Its main use is as a building material/ in the manufacture of iron
Powdered limestone + high temperature+ sand+ sodium carbonate= glass
powdered limestone + powdered clay + heat= cement
cement powder + water + sand +gravel= concrete
Limestone + strong heating= quicklime (calcium oxide) + carbon dioxide (thermal decomposition)
To make lots of quicklime we use a lime kiln
1) fill the kiln with crushed limestone
2) heat it strongly with a supply of hot air
quicklime comes out of the bottom of the kiln, waste gases leave at the top.
Usually the kiln rotates to ensure that the limestone is thoroughly mixed with the stream of hot air and it therefore decomposes completely. 1.3 Decomposing carbonates
Calcium is in group two, as is magnesium, so we can expect magnesium carbonate to have the same properties as calcium carbonate (they both decompose)
The behaviour of carbonates
Calcium carbonate (2) / Magnesium Carbonate (2) / Zinc Carbonate/ Copper Carbonate DECOMPOSE (Y)
Potassium Carbonate(1) / Sodium Carbonate (1) DO NOT DECOMPOSE (N)
From looking at these results we could say that they suggest that group two...
Please join StudyMode to read the full document