Elemental Bromine (Br)
recently began a new hobby; collecting elements. Of course
such a hobby comes a lot of chemistry. Especially due to the fact that
whatever elements I can isolate by myself, I will. I believe it is much
more fulfilling and educational to isolate an element yourself than
purchase it from some online retailer in a little vial or ampoule. Of
course with chemistry there is inherent danger. So this disclaimer is
Bromine is a VERY dangerous element. Even small concentraions of it in
the air can kill you. DO NOT ATTEMPT THIS SYNTHESIS unless you are a
highly qualified chemist. It is also HIGHLY reactive and will react
vigioursly with nearly any substance other than glass that it comes
into contact with.
Bromine is one of those elements I have the utmost respect for. I
seriously considered not synthesizing it at all due to how dangerous it
Here is the outline I wrote myself for
reactants were as follows:
- Sodium Bromide. Found at many pool stores to be used
in hot tubs if I remember correctly.
This reaction was not performed with stoichiometric quantities since
only a very small amount was needed for my element display. In fact,
the smaller the sample the better, because Bromine is SCARY stuff!
A massive amount of though went into this reaction, and it was not
taken lightly due to the immense dangers of elemental Bromine. All
proper safety equipment including protective clothing, gloves, a full
face shield, and a respirator were utilized. A bucket of Sodium
Thiosulfate solution was nearby to neutralize any Bromine just in case
an accident occurred.
First a small amount of Sodium Bromide was added to a test tube which
acted as the reaction vessel. Approximately .5 gram was used. To this a
small quantity of Manganese Dioxide was used to act as the oxidizer in
the reaction, again approx .5 gram was used. After moving outside with
a large fan blowing any fumes away from my workspace, approximately 5
mL of Hydrochloric acid was added to the NaBr/MnO2 mixture. No
immediate reaction was noted. This was clamped onto a labratory stand,
and setup for simple distillation into a chilled test tube. The
receiving apparatus (the test tube) was surrounded by an ice bath to
minimize evaporation of the elemental Bromine formed. Upon gently
heating the reaction vessel thick dark red clouds of Bromine vapor was
visible. These traveled up the tube and eventually through the simple
distillation apparatus into the receiving vessel,
which began collecting the elemental Bromine.
Here is a picture of the setup:
And here is the small ampoule of elemental Bromine collected with a
small amount of liquid Bromine at the bottom:
All lab equipment used was properly neutralized with a Sodium
Thiosulfate solution to destroy any remaining Bromine. The Bromine
actually destoryed the rubber stopper used in the reaction vessel,
which is a testament to its corrosive properties.
This was a truly terrifying reaction to perform, even given my massive quantities
of safety gear. However, it was a successful reaction with no incidents
and the Bromine is not sitting neatly in its ampoule (inside of a glass
vial) on my element display.