Chemistry - Tests

Tests for anions, aqueous cations, gases and flame tests for metal ions

carbonate

carbonate

test: add dilute acid

test result: effervescence, carbon dioxide produced

chloride

test: acidify with dilute nitric acid, then add aqueous silver nitrate

test result: white ppt.

bromide

test: acidify with dilute nitric acid, then add aqueous silver nitrate

test result: cream ppt.

nitrate

test: add aqueous sodium hydroxide, them aluminium foil; warm carefully

test result: ammonia produced

sulfate

test: acidify, then add aqueous barium nitrate

test result: white ppt.

ammonium

effect of aqueous sodium hydroxide: ammonia produced in warming

effect of aqueous ammonia: -

calcium

effect of aqueous sodium hydroxide: white ppt., insoluble in excess

effect of aqueous ammonia: no ppt. or very slightly white ppt.

copper (II) - aqueous cation

effect of aqueous sodium hydroxide: light blue ppt., insoluble in excess

effect of aqueous ammonia: light blue ppt., soluble in excess, giving a dark blue solution

iron (II)

effect of aqueous sodium hydroxide: green ppt., insoluble in excess

effect of aqueous ammonia: green ppt., insoluble in excess

iron (III)

effect of aqueous sodium hydroxide: red-brown ppt., insoluble in excess

effect of aqueous ammonia: red-brown ppt., insoluble in excess

zinc

effect of aqueous sodium hydroxide: white ppt., soluble in excess, giving a colourless solution

effect of aqueous ammonia: white ppt., soluble in excess, giving a colourless solution

ammonia

test and test result: turns damp red litmus paper blue

carbon dioxide

test and test result: turns limewater milky

chlorine

test and test result: bleaches damp litmus paper

hydrogen

test and test result: ‘pops’ with a lighted splint

oxygen

relights a glowing splint

lithium

red flame

sodium

yellow flame

potassium

lilac flame

copper (II) - metal ion

blue-green flame