This is one of the freakiest and most beautiful reactions in chemistry.
It’s known as the Belousov-Zhabotinsky reaction. And it shows chemicals left in a petri dish forming beautiful and ever-changing patterns seemingly out of nowhere. This is really happening – there is no special effects or camera trickery.
This incredible property of certain chemical mixtures was discovered by a Russian chemist Boris Belousov in the1950s.
Belousov was working on understanding how glucose was absorbed by the body. And as chemists are prone to do was mixing various chemicals together.
On this particular day he had made a clear and colourless solution. As he mixed in the final chemical, the whole solution changed colour.
Now this isn’t particularly remarkable. If, for instance, we mix ink into water, it changes colour.
But then something happened that made no sense at all – the mixture began to go clear again.
Belousov was astounded. Chemicals can mix together and react.But they shouldn’t be able to go back on themselves, to apparently unmix without intervention.
You can change from a clear mixture to a coloured mixture, fine. But surely not back again?
And it got weirder.
Belousov’s chemicals didn’t just spontaneously go into reverse. They oscillated.
They switched back and forth from coloured to clear, as if they were being driven by some sort of hidden chemical metronome.With meticulous care, he repeated his experiments again and again.
It was the same every time. His mixture would cycle from clear to coloured and back again, repeatedly. He’d discovered something that was almost like magic,a physical process that seemed to violate the laws of nature.
Convinced he’d discovered something of great importance, Belousov wrote up his findings. But when he submitted his paper to a leading Russian scientific journal it was rejected. The editor of the journal told Belousov that his findings in the lab were quite simply impossible. He said they contravened the fundamental laws of physics.The only explanation was that Belousov had made a mistake in his experiment, and the work was simply not fit for publication.
The rejection crushed Belousov. Deeply insulted by the suggestion his work had been botched, he abandoned his experiments and gave up science altogether.
In the early 1960s, Anatoly Zhabotinsky noticed the same phenomenon. He did manage to convince the world of their validity and so these incredible reactions are now known as the Belousov-Zhabotinsky reaction.
The reactions are physical proof of Alan Turing’s groundbreaking research on morphogenesis and have since been shown to be at the heart of many natural phenomenon – such as how animals, like leopards and zebras, get their peculiar markings.