formulations, pure and impure substances

Pure substance=

A single element or compound, made up of only type of substance

Impure substance=

A mixture of substances

Melting point=

Temperature at which solid turns to liquid

Boiling point=

Temperature at which liquid turns to gas

Formulation

A mixture designed for a specific purpose, and has set proportions

Melting and boiling point of pure substances

Sharp (exact)

E.g. pure water b.p=100 and m.p=0

Melting and boiling point of impure substance

Melt and boil over a range of temperatures

Impurities decrease the melting point and increase boiling point

What do formulations have

Set proportions of each part of a mixture to ensure it has the desired properties

Examples of formulations

Paint

Cosmetics

Fertilisers

Medicine

Graph of an impure substance

No flat lines