Chemical Test Summary
Gases
Oxygen
Glowing splint
Relights
Hydrogen
Burning splint
Squeaky “pop”
Carbon Dioxide
Lime Water
Turns Milky
Chlorine
Blue litmus paper
Moist starch - Iodide paper
Bleached
Turns blue
Ammonia
Red litmus paper
Turns blue
Water
Anhydrous copper (II)
sulphate
White to blue
Physical: boiling point
100oC, Freezing point 0oC
Cations
Flame Tests
Dip clean platinum or nichrome wire into hydrochloric acid
Dip the wire into solid compound
Lithium (Li+)
Red flame
Sodium (Na+)
Yellow flame
Potassium (K+)
Lilac flame
Calcium (Ca2+)
Red-Orange flame
Copper (Cu2+)
Blue Green
ONLY GAS WHERE LITMUS PAPER IS USED
Ammonium (NH4+)
Add Sodium Hydroxide (aq) to solid & warm
Test gas with Damp UI paper
●
●
●
Turns red litmus paper Blue (alkali)
Pungent smelling gas produced
NH3 + H2O
TESTS FOR METAL CATION HYDROXIDE
Add Sodium Hydroxide (aq)
● The precipitate will be Metal Cation Hydroxide
Copper
blue
Iron (II)
green
Iron (III)
brown
Anion
Add dilute Nitric Acid to remove carbonate ions
Add drops of Silver Nitrate (aq)
Silver Halide produced
Chloride (Cl-)
White
(AgCl)
Bromide (Br-)
creamy
Iodide (I-)
yellow
SULPHATE:
Acidified Barium Chloride (aq)
Sulphate (SO42-)
white
Add Hydrochloric Acid (aq)
Bubble the gas into limewater
Carbonate (CO32-)
Limewater turns milky