purity and formulations

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Purity and Formulations

Chemical analysis

Instruments and methods used to separate, identify, and quantify different substances.

separate = chromatography, filtration, crystallisation, distillation

identify = chemical tests

pure substance : contains only one type of compound or element, not mixed with any other compound or element

e.g. pure water, only contains water molecules

only pure substances melt and boil at specific temperatures

e.g. water boils at 100*C

impure don't have specific melting or boiling points

Having impure substances lowers melting point and increases boiling point

e.g. salt water mp -2*C bp 100.5*C

formulations - mixtures prepared using a specific formula that have precise amounts of diff. components and have a particular function.

fuels, cleaning agents, paint, medicines, alloys, fertilisers, food and drink

diff components are always present in the same proportions

each component might contribute a different property