Description of experiment
Below follows a plain text transcript of the selected experiment.
Needed compounds:
-----------------
sodium sulfite : Na2SO3
sulphuric acid : H2SO4
potassium bromate : KBrO3
Class:
------
elem=Br
redox
Summary:
--------
Bromate is reduced by sulfite quickly in acidic environments. When an
excess amount of bromate is used, then bromine is formed. When an excess
amount of sulfite is used, then the bromine is reduced further to bromide.
Description:
------------
Dissolve some KBrO3 in dilute H2SO4 (appr. 2 mol/l) and add a small amount
of solid sodium sulfite (hepta hydrate): The sodium sulfite quickly dissolves
and the liquid becomes brown/red. The gas mixture also is coloured by the
released bromine.
Add more sodium sulfite: The liquid becomes colorless and a clear smell of
SO2 is observed.