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Go to Brilliant.org/SciShow to  check out their Chemical Reaction course and for 20% off an  annual premium subscription. [♪ INTRO] If you asked someone who  discovered catalysis, most people would answer with ‘what’s catalysis?’! Well, catalysis is a chemical process  that’s critical to our modern lives.

It happens in factories, cars, oh,  and also inside every living thing. Discovering how it all worked back in the  late 18th Century wasn’t an easy feat, but Elizabeth Fulhame was up for the challenge. Most chemistry students learn that catalysis was discovered in 1835 by Jöns Jacob Berzelius.

And although he certainly gave a name  to the process, the surprising chemical behavior was actually documented some  40 years earlier by a particularly strong-minded scientist named Elizabeth Fulhame. But before we get into that,  let’s set some foundations first. Chemical reactions are happening  all around us, all the time.

But all reactions need some energy to get them started, known as activation energy. Just like you need to summon  a little extra energy to get out of bed before you can go to work! But if reactions need some help to go  over that hump, there are substances, called catalysts, that allow reactions  to get around that activation energy, so they can happen quicker, and at lower  temperatures, than they normally would.

In most cases, catalysts work by providing a surface for reaction ingredients  to stick to while they react. Once the molecules are stuck to the catalyst  in the right positions, they are much more likely to break and form bonds  than if they were floating freely. That means that even with all the  chemistry happening around them, the catalysts themselves aren’t used up.

And these catalysts are  used pretty much everywhere. They’re used to make about  80% of manufactured products, and about 90% of industrial chemicals. They’re in places like your car in the  shape of a catalytic converter, where the platinum surface helps to  speed up the transformation of super toxic gases to slightly less dangerous ones!

You also have catalysts inside your cells  as protein catalysts, known as enzymes, which are responsible for a bunch of things like digestion, respiration, and cell repair. Without them, all these processes would  simply happen too slow for us to survive. So catalysts are pretty important for a  bunch of things, but discovering how they worked in the late 18th Century was challenging.

And that’s where Elizabeth Fulhame comes in. Although there isn’t much information  about her, we do know that she had the time and the means to pursue her interests  as an experimental chemist, even though this was a very much a  male-dominated field at the time. Her main mission was to find  a way to dye cloth with gold.

Her idea was to deposit the metals, like  gold, onto fabrics by starting out with a metal-salt solution and  then adding electrons to the metal through a process called reduction. Reduction happens when things like metal  are exposed to a reducing agent, which passes electrons into  materials by oxidizing itself. And Fulhame had hopes that it would help  the metal bind to the cloth, after dipping fabric in the solution, leaving  behind lustrous metallic gold.

These kinds of interactions: the donation  of electrons in reduction, and the loss of them in oxidation, weren’t very well  understood at the time. In fact, electrons wouldn’t even be discovered  for another hundred years! So, when Elizabeth Fulhame published 14  years of her work in a single essay in 1794, she talked about it in terms of  the chemicals involved: the metals, the reducing agents like hydrogen,  and oxidizing agents like oxygen.

In her essay, she reported some success  in dying cloth with gold and also in embellishing maps with gold and  silver to mark cities and rivers “as much as her finances allowed.” But much of her essay is devoted to the  hundreds of experiments she tried, which have since been described by other  chemists as both meticulous and tedious! In these experiments, Elizabeth exposed  metallic salts to various reducing agents, like hydrogen or charcoal, under different  conditions, trying to get them to react. She exposed metals to reducing  agents without using a solvent, and to others she added solvents  like water, ether, or alcohol.

And Elizabeth found that in many cases,  high concentrations of water were needed for reaction, as she saw little change in  the experiments with small amounts of it. More importantly, she was able to  show that, with water in the mix, the reduction of metals could be  done at room temperature and colder. Before then, people thought reducing  metals could only be possible by heating them, a lot, like in a furnace, to overcome  the activation energy for the reduction.

Not only that, but the water still seemed  to be there at the end of the reaction. Elizabeth supposed that the water was  broken down into its components, hydrogen and oxygen, which were used up and  regenerated over the course of the reaction, likening it to a phoenix rising from the ashes. But some turned the phoenix analogy against  her, claiming that her theories were as fanciful and fabulous as the phoenix itself.

However, the essay did contain the first  real steps towards understanding catalysis. Today we know that the metal reduction that Fulhame was testing was being catalyzed by water. The way water worked during the reaction was by binding to the positive metal  ions, so they could react and combine easily with an electron  from the reducing agent.

So, although her mechanism for water’s involvement wasn’t quite right,  her observations were spot on. She was the first to describe  catalysis, reduction, oxidation, and equilibrium in a very modern sense. When Berzelius came to the topic 40  years later, whether he knew about her work or not, she had already helped to steer the course of chemistry into familiar  waters, way ahead of her time.

And catalysis is still something  we’re learning about today. The 2021 Nobel Prize in Chemistry was awarded for the development of asymmetric  organocatalysts, which, although it sounds pretty advanced, it  still relies on the foundations that Elizabeth Fulhame uncovered  more than 225 years ago. And if you would like to keep exploring  the other nuts and bolts of chemistry, you should check out today’s sponsor Brilliant!

Brilliant is an online  learning platform with courses about science, engineering,  computer science and math. In there you can find courses like “The  Chemical Reaction,” where you can learn more about catalysis, but with  fully interactive puzzles. Like traversing the peaks and  valleys of reaction landscapes.

If you’d like to give Brilliant a try,  you can sign up at Brilliant.org/SciShow to save 20% off an annual premium subscription. Checking them out supports us too, so thank you! [♪ OUTRO]