chem - testing for ions

hydrogen test

lit splint to gas- squeaky pop

Oxygen test

glowing splint- relights

carbon dioxide

bubble through limewater- limewater turns milky

chlorine test

expose damp blue litmus paper- litmus paper bleached white

flame test method

clean nichrome wire loop, dip in dilute Hcl, dip in sample, place in bunsen flame

lithium

Li+ - crimson red flame

sodium

Na+- yellow flame

potassium

K+ - lilac flame

calcium

Ca+- orange-red flame

copper (flame)

Cu2+ - green flame

barium

ba2+ - apple green flame

solution tests

add a few drops of NaOH (sodium Hydroxide) to the solution

aluminium

Al3+ white pct- soluble in excess

calcium

Ca2+ - white pct

magnesium

Mg2+ - white pct

copper

Cu2+ - blue pct

iron (2)

Fe 2+ - green pct

iron (3)

Fe3+ - brown pct

zinc

Zn2+ - white pct - dissolves in excess

anion tests

chloride, bromide, sulfate —> acidify with dilute HN03 (nitric acid) then add AgNO3 (silver nitrate)

chloride

white pct - soluble

bromide

cream pct- soluble in concentrated

iodide

yellow pct - insoluble

sulfate SO42-

acidify w dilute hcl, then add BaCl2 - white pct

nitrate No3-

add NaOH and aluminium powder, warm gently - ammonia gas given off, plugent smell of ammonia + damp red litmus turns blue

carbonate CO32-

add dilute acid (eg Hcl) - co2 gas given off, effervescnece, turms limewater milky