| |
Anion Lab Manual
II. The
gas evolved during heating or reaction with dilute
acids
|
Process
|
Gas liberated
|
Possible Anion present
|
| 1.
Heating |
CO2 |
Carbonate,
CO32-
Hydrogencarbonate, HCO3- |
| |
O2 |
Nitrate, NO3-
Oxygen rich compounds e.g. Pb3O4
, H2O2 |
| |
NO2 |
Nitrate,
NO3-
of metals below sodium in the reactivity series
|
| |
SO2 |
Sulphates that
are less stable to heat e.g. FeSO4.7H2O |
| 2. Addition of
dilute acid |
CO2 |
Carbonate, CO32- |
| |
SO2 |
Sulphate,
SO32- |
|