Testing For Substances

AQA syllabus for testing for substances. Includes (some): elements, flame tests, cations, and random others

?

Cations

Li: bright-red

Na: yellow-orange

K: lilac

Ca: brick-red

Ba: green

^All above require flame test, NICHROME WIRE

NH(4): sodium hydroxide + heat: produces NH(3)

1 of 3

Others

Al: white precip: does dissolve into excess NaOH

Ca: white precip: doesn't dissolve into excess NaOH: brick-red in flame test

Mg: white precip: doesn't dissolve into excess NaOH: no colour in flame test

Cu: light blue precip

Fe(2+): green precip

Fe(3+): orange-red-brown precip

^The above required acidified sodium hydroxide solution.

Cl: white precip

Br: cream precip

I: yellow precip

^The above require silver nitrate solution

SO(4): dilute nitric acid and then add barium chloride: white precip of barium sulphate forms

NO(3): aluminium powder, NaOH and warm: produces NH(3)

2 of 3

Elements and Carbonates

Oxygen: relights a glowing splint

Hydrogen: squeaky pop when presented with a lit splint

Cardon Dioxide: bubble through lime-water: white precip (Calcium Carbonate)

Chlorine: bleaches DAMP litmus paper

Ammonia: turns DAMP red litmus paper blue

Alkenes: decolourises bromine water

Water: anhydrous copper sulphate: turns blue

Copper Carbonate: heat: turns black

Zinc Carbonate: heat: turns yellow, then back to white if allowed to cool

3 of 3

Comments

No comments have yet been made

Similar Chemistry resources:

See all Chemistry resources »See all Testing and analysing substances resources »