C12 - Chromatography + pure substances Flashcards
pure substance
made up of one substance only
either an element or compound
impure
mixture of 2 or more elements/compounds
identify pure substances
by their boiling points/ melting
pure substance bioling point
sharp
impure substances boiling point
vary over a range
impurities effect on boiling and melting points
-lowers melting point
-raises boiling point
test for pure water
-melts at 0 degrees celsius
-boils at 100 .c
purer the compound =
narrower the melting point range
formulation
-mixture that has been designed to produce a useful product
eg of formulations
-paint
-medicinal drugs
-fuels
-fertilisers
-cosmetics
-food products
paint formulations
-pigment
-binder
-solvent
pigment
-provides colour
binder
allows paint to attach to object and dry to form a protective film
solvent
-help pigment/ binder to spread well
cleaning products: surfactant
detergent