chemical analysis

What is the mobile phase in chromatography?

the solvent e.g water

what is the stationary phase in chromatography

the chromatography paper

equation for Rf value in chromatography

distance substance moved/ distance solvent moved

what is the test for hydrogen

Put a lit splint where the gas is, for a positive result there will be a squeaky pop

what is the test for oxygen

a glowing spring will relight if it is present

what is the test for carbon dioxide

When bubbled through limewater it turns the limewater cloudy

what is the test for chlorine

Bleaches damp blue litmus paper

what is a positive flame test for lithium

crimson

what is a positive flame test for sodium

yellow

what is a positive flame test for potassium

lilac

what is a positive flame test for calcium

orange-red

what is a positive flame test for copper

green

what is the test for metal ions

sodium hydroxide

what happens to aluminium, calcium and magnesium in the NaOH test

all form a white precipitate, however aluminium hydroxide produced will dissolve in excess NaOH

what is formed with copper II in the NaOH test

blue precipitate

what is formed with iron II in the NaOH test

green precipitate

what is formed with iron III in the NaOH test

brown precipitate

how to test for carbonates

they react with acid to form carbon dioxide

what is the test for the different halide ions?

silver nitrate and nitric acid

what is a positive silver nitrate test for chlorine

white precipitate formed (Chilly Willy)

what is the positive silver nitrate test for bromide

cream precipitate formed (Big Cocks)

what is the positive silver nitrate test for iodide

yellow precipitate formed (Impale You)

what is the test for sulphate ions

when mixed with barium chloride and hydrochloric acid it forms a white precipitate

how does flame emission spectroscopy work

wavelengths of light emitted by a flame are analysed and can be used to identify specific ions

why is flame emission spectroscopy better than normal flame tests

more accurate, sensitive and faster