IGCSE Chemistry Ion and Gas Tests

Potassium (K+) ions

Lilac Flame

Lithium (Li+) ions

Red flame

Sodium (Na+) ions

Yellow flame

Calcium (Ca2+) ions

Red-Orange flame

Copper (Cu2+) ions

Green flame

Iron (Fe2+) ions

Green PPT (with NaOH)

Iron (Fe3+) ions

Brown PPT (with NaOH)

Copper (Cu2+) ions

Blue PPT (with NaOH)

Sulfate (SO4 2-) ions

White PPT (with acidified Barium Chloride)

Carbonate (CO3 2-) ions

Gas produced (when reacted with acid) turns limewater cloudy

Chloride (Cl-) ions

White PPT (with acidified Silver Nitrate)

Bromide (Br-) ions

Cream PPT (with acidified Silver Nitrate)

Iodide (I-) ions

Yellow PPT (with acidified Silver Nitrate)

Ammonium (NH4+) ions

Gas produced (when warmed with NaOH) turns red litmus paper blue

Oxygen (O2) gas

Relights a glowing splint

Carbon Dioxide (CO2) gas

Turns limewater milky/cloudy

Hydrogen (H2) gas

Lit splint produces a squeaky pop

Ammonia (NH3) gas

Moist red litmus paper turns blue

Chlorine (Cl2) gas

Moist blue litmus paper turns red then white (bleaches)

Chemical Test for Water

Anhydrous Copper Sulfate turns from White to Blue

Physical Test for pure water

boils at 100 degrees, freezes at 0 degrees

Limewater is a solution of ...

Calcium Hydroxide

The reason limewater turns cloudy with Carbon Dioxide is because _____________ is formed?

Calcium Carbonate