CHEMISTRY

Subdecks (7)

Elements are made of only one atom
Compounds are substances made of two or more different elements that are chemically joined
Mixtures contain atoms that are not chemically joined
Mixtures can be separated by physical processes that are: Distillation, Evaporation, Chromatography and filtration.
In paper chromatography, a drop of the mixture is placed
on chromatography paper and the paper is then placed in
a beaker of solvent (e.g. water), with the level of the solvent
just below the level of the spot.
The solvent soaks into and then moves up the paper. Any
soluble substance in the pigment dissolves in the solvent and
travels up the paper with it. The most soluble substances
travel the furthest. The substances can be identified by how
far they have travelled.
To identify oxygen you place in the presence of a glowing splint. If oxygen is present = the glowing splint relights
To identify hydrogen you place in the presence of a lit splint. If hydrogen is present = you will hear a squeaky pop
To identify carbon dioxide you bubble the gas through limewater. If CO2 is present = Limewater turns milky