A LEVEL CHEMISTRY - COLOURS OF COMPOUNDS

COLOURS OF COMPOUNDS

A few names of compounds, their colours, their special characteristics (if any), etc.
 You'll find this information useful in Acids, Bases, and Salts; Analytical Chemistry; and in the differentiate between two salt/acids/compounds questions.
 --> PbCl2 - white chalky ppt; insoluble in cold water, soluble in hot water.
 --> AgCl - white curdy ppt; insoluble in hot and cold water
 --> ZnO/PbO - yellow when hot, white when cold
 --> BaSO4 - white ppt; insoluble in all dilute mineral acids
 --> PbSO4 - white ppt; insoluble on heating (or when hot)
 --> Zn(NO3 )2 - white
 --> CuSO4 .5H2O - blue
 --> CuSO4 (after losing water of crystallization) - white amorphous
 --> CuCO3 - green
 --> Cu - reddish/pink deposit
 --> CuO - black
 --> MnO2 - black
 --> FeCl3 - reddish brown; NOTE: Name a reddish brown deliquescent salt (always FeCl3 )
 --> FeSO4 - dirty green
 --> KMNO4 - purple/violet
 --> K2Cr2O7 - orange
List of Gases:
 --> I2 - violet
--> Br2 - reddish/brownish gas
 --> NO2 - reddish brown gas
 --> Cl2 - greenish yellow gas; NOTE: NOT yellowish green
 --> SO2 - burning sulphur smell
 --> NH3 - green flame when burnt in oxygen
 --> NH3 , HCl, CO2 , SO2 - colorless gas with pungent odor
 --> HNO3 (pure) - colorless
 --> HNO3 (in sunlight) - yellow
List of Colored Ions:
 --> Cupric Cu2+ - Blue
 --> Chromium Cr3+ - Dark green
 --> Nickel Ni2+ - Green
 --> Ferrous Fe2+ - Light green
 --> Ferric Fe3+ - Brown
 --> Manganese Mn2+ - Light pink
 --> Cobalt Co2+ - Pinkish violet
 --> Permanganate MnO4 - - Pink
 --> Chromate CrO4 2- - Yellow
 --> Dichromate Cr2O7 2- - Orangish yellow NOTE: All salts of Na, K, NH4 are white