Рет қаралды 72,244
We show how to make hydrobromic acid.
Hydrobromic acid is the bromine analogue of hydrochloric acid. While too expensive to use as much as hydrochloric acid, it's often used when the bromine element itself is needed. For example a major use is the synthesis of organobromine compounds like the ones we used in our grignard reactions.
To make it, we start with 400mL of water and add to it 250g of sodium bromide. Sodium bromide is available as a bromine source for swimming pools. To this we add 200mL of sulfuric acid, I got mine from drain opener.
The mixture is stirred until everything is dissolved and then cooled to freezing to crystallize out the byproduct sulfates and bisulfates.
The filtrate is then distilled until half the volume has been transferred and then allowed to cool. More crystals should crash out. This is filtered again and the filtrate is again distilled.
The distillate is then fractionally distilled to obtain constant boiling acid at around 124-126 celsius.
If the acid is yellow or orange, this indicates bromine formation. To remove it sulfur is added (1g per 100mL) and then distilled. The bromine-free distillate will have colloidal sulfur in it so it can be refluxed for an hour to drive the sulfur into the column.
Alternatively sodium metabisulfite can be added in small amounts until clear. Then distilled again to leave behind the sodium bisulfates.
Related videos
make hydrobromic acid: • Make Hydrobromic Acid
Donate to NurdRage!
Through Patreon (preferred): / nurdrage
Through Bitcoin: 1NurdRAge7PNR4ULrbrpcYvc9RC4LDp9pS
Glassware generously provided by www.alchemylabs...
Use the discount code "nurdrage" for a 5% discount.
Twitter: / nurdrage
Reddit: / nurdrage
Facebook: / nurdrageyoutube
Instagram: / nurdrageyoutube