Chemistry Tests

Hydrogen Test

lit splint at mouth of test tube -> squeaky pop sound

Oxygen Test

glowing splint at mouth of test tube -> relights

Carbon Dioxide Test

delivery tube -> limewater tube -> limewater goes cloudy

Chlorine Test

damp litmus paper -> put at mouth of test tube -> bleaches red side -> bleached blue side after turning it red

Ammonia test

damp RED litmus OR UI at mouth of test tube -> ammonia turns it blue

Li+ colour

red

Na+ colour

yellow

K+ color

lilac

Ca2+ colour

orange-red

Cu2+ colour

blue-green

Cu2+ + NaOH ->

Blue precipitate

Fe2+ + NaOH

Green precipitate (orange at top)

Fe3+ NaOH

Orange-brown precipitate

NH4+ + NaOH

No precipitate, ammonia gas produced

carbonates (C03^-2) test

1) Add dilute HCl to SOLID CO2-3
2) look for fizzing
3) If sample fizzes, repeat test but use delivery tube to bubble through limewater

The limewater should go cloudy

Sulfates (SO4 2-) test

1) Magnesium SULFATE solution in test tube
2) Add dilute HCl (to remove other anions)
3) Add BARIUM CHLORIDE solution dropwise with pipette
4) White precipitate = sulfate ions

White precipitate formed

General test for halides

1) Add 1 pipette squirt of DILUTE NITRIC ACID to test tube of halide solution
2) Add silver nitrate solution
3) observe precipitate colour

Cl- halide precipitate

White

Br- halide precipitate

Cream

I- halide precipitate

Yellow