Discovery of Bromine

Bromine compounds have been used since ancient times.

In the first century AD Pliny describes one of the world’s first chemical industries: dye factories making Tyrian purple. Tyrian purple (or royal purple) is an ancient purple dye obtained from a marine mollusk. A major component of the dye is the compound 6,6′-dibromoindigo. 

Three people are significant in the story of the element bromine’s discovery.

First there’s German chemist Justus von Liebig, one of most famous chemists of his time. Liebig could have been credited with the independent discovery of bromine, but he squandered the opportunity.

In 1825 a salt maker sent Liebig a sample of salt spring waters from the German town of Bad Kreuznach, asking for an analysis.

The sample had a relatively high amount of bromine in it, which Liebig isolated. Without considering the substance too seriously, he concluded it was a compound of iodine and chlorine.

Only when bromine’s existence had been announced did an anguished Liebig return to the red-brown liquid to study it closely.

He then placed the bottle in his ‘mistakes cupboard’ to remind himself that preconceived ideas ruined his chance of discovering something new and to try not to make the same mistake again.

The next name in the story of bromine is Carl Lðwig (Loewig), who discovered bromine in 1825, while still a chemistry student at Heidelberg University, Germany.

Lðwig’s home town was Bad Kreuznach, where Liebig’s sample had come from. Lðwig had taken water from a salt spring in Bad Kreuznach and added chlorine to the liquid. He shook the solution with ether and found a red-brown substance dissolved in the ether. Lðwig evaporated the ether to leave a red-brown liquid: bromine.

His professor at Heidelberg asked Lðwig to prepare more of this substance for testing. By the time Lðwig had done this it was 1826 and a final name – Antoine Balard – had taken over the story of bromine’s discovery.

In 1824 Antoine Balard, aged 21, was studying the plant life in a salt marsh in Montpellier, France. He became interested in salt deposits he saw and began investigating them.

He took brine (sea water in which salts have been concentrated by evaporation of water) and crystallized salt from it. He took the remaining liquid and saturated it with chlorine.

He then distilled the solution to leave a dark red liquid.

Alert to the possibility that he had found something very interesting, Balard gave the French Academy of Science a sealed envelope containing his initial results in 1824.

He finally published his results in 1826, providing evidence that the substance he had discovered was a new ‘simple body’ – i.e. an element, not a compound.

As first to publish, he became bromine’s discoverer. Ironically, like Liebig, his first idea was that the substance was a compound of chlorine and iodine.

The French Academy named the new element after the Greek bromos for ‘stench’ because bromine, quite simply, stinks.

نظرات شما عزیزان:

نام :

آدرس ایمیل:

وب سایت/بلاگ :

متن پیام:

نظر خصوصی

 کد را وارد نمایید:

 

 

 

عکس شما

آپلود عکس دلخواه: