Description of experiment
Below follows a plain text transcript of the selected experiment.
Needed compounds:
-----------------
sulphuric acid : H2SO4
potassium bromate : KBrO3
Class:
------
elem=Br
redox
Summary:
--------
Bromate reacts with concentrated sulphuric acid, releasing bromine and a
gas (probably this is oxygen).
Description:
------------
Add some solid KBrO3 to some concentrated H2SO4 (appr. 96% by weight): The
solid starts bubbling and bromine is formed (liquid becomes red/brown and
a red/brown gas is formed). The liquid starts foaming. Probably the bromate
is converted to HBrO3, which decomposes to bromine, oxygen and water. The
foaming of the liquid is assumed to be due to formation of oxygen.
BEWARE: This must be done with a minute quantity of potassium bromate, a few
cubic mm at most, on which a large drop of H2SO4 is put!