Chapter Content
Okay, so, where to even begin with the whole story of early chemistry? It's kinda wild, right? You always hear that chemistry really became, like, a legit science around 1661, because of this guy Robert Boyle. He wrote this thing called "The Sceptical Chymist," which, apparently, was the first time someone really tried to separate actual chemists from, you know, the alchemists, who were trying to turn lead into gold and stuff. But it wasn't like a clean break, you know? It was slow, and people were still dabbling in both for a while.
Like, even in the 1700s, you had guys who were writing, like, serious books about minerals, but they also thought they could, like, become invisible if they just had the right ingredients. Crazy!
One of the weirdest, and maybe coolest, early discoveries was this dude Hennig Brand back in 1675. He was, like, obsessed with the idea of getting gold from, get this, human pee. Yeah, I know. He thought because pee was yellow-ish, it must somehow be connected to gold. So, he collects, like, 50 buckets of the stuff and stashes it in his basement for months. And after doing all sorts of crazy things to it, he ends up with this, like, waxy, translucent substance. No gold, obviously. But the weird thing is, it started to glow in the dark! And sometimes, it would just burst into flames when it was exposed to air. Whoa!
They called it phosphorus, which is Greek and Latin for "light-bringer." People saw the potential, you know, business-wise, but it was so hard to make. It was crazy expensive, like, more expensive than gold! At first, they tried to get soldiers to donate their... raw material, let's say, but that didn't really work for mass production.
Then, this Swedish chemist named Carl Wilhelm Scheele comes along in the 1750s and figures out how to make phosphorus without using, you know, pee. Because of this, Sweden became a major producer of matches, which is kinda cool.
Now, Scheele, this guy was seriously unlucky. He was just a regular, low-level pharmacist, and he managed to discover, like, eight different elements – chlorine, fluorine, manganese, barium, molybdenum, tungsten, nitrogen, and oxygen – with, like, hardly any fancy equipment. But he never got any credit! Either people didn't notice, or someone else would discover the same thing and publish it first. He also found all sorts of useful compounds, like ammonia, glycerin, and tannic acid. And he was the first to think of using chlorine as a bleach! All this stuff, and other people got rich off it.
Apparently, Scheele had this thing where he would taste everything he was working with. Like, even the nasty, poisonous stuff, like mercury, hydrocyanic acid, and acetonitrile. Acetonitrile is super toxic; some scientist even used it as the perfect poison in a thought experiment, like, 150 years later. Anyway, Scheele's recklessness eventually killed him. He was found dead at his workbench in 1786, surrounded by toxic chemicals. Yikes!
If the world was fair, and if everyone spoke Swedish, Scheele would be, like, super famous. Instead, all the credit went to chemists who were usually, well, English. He discovered oxygen back in 1772, but he couldn't get his paper published in time. So, Joseph Priestley gets the credit for discovering it in 1774, even though Scheele did it first. And almost every textbook says that Humphry Davy discovered chlorine, even though Scheele discovered it 36 years earlier. That's rough.
So, you go from people like Isaac Newton and Robert Boyle to Scheele and Priestley, and a century passes. Chemistry's made a lot of progress, but it still had a long way to go. You had all these scientists searching for stuff that didn't even exist. They were looking for phlogiston, which they thought was the thing that made stuff burn, and they thought there was, like, a special "vital force" that gave life to non-living things. Nobody knew where this "vital force" was, but they thought you could, like, activate it with electricity, which is where Mary Shelley got the idea for Frankenstein. And that's why chemistry ended up being divided into organic and inorganic – organic being stuff that was thought to have that "vital force" and inorganic being stuff that didn't.
What chemistry really needed was someone to, like, modernize it. And that person was Antoine-Laurent Lavoisier, from France. He was born in 1743 and he bought himself a share in this really unpopular organization that collected taxes for the government. Lavoisier himself was supposedly pretty nice and fair, but the organization wasn't. It only taxed poor people, not rich people, and they were pretty heavy-handed about it. But Lavoisier liked it because it gave him tons of money to do science.
He married his boss's 14-year-old daughter three years later. Apparently, it was a good match. She was super smart and helped him a lot with his work. Even though they were busy with work and social stuff, they still spent, like, five hours a day – two in the morning and three at night – plus Sundays, doing science. He also managed to be a gunpowder commissioner, oversee the construction of a wall around Paris to stop smugglers, and help develop the metric system. He also co-wrote a book on chemical naming, which became, like, the bible for standardizing element names. Busy dude.
He was also part of the Royal Academy of Sciences and he seemed to be involved in everything – hypnotism, prison reform, bug breathing, the water supply for Paris, you name it. And Lavoisier was kinda, well, a jerk. One time, he totally dismissed a young scientist's theory about combustion, and the guy never forgave him. His name was Jean-Paul Marat.
Here's the crazy thing: Lavoisier never actually discovered an element. Like, in an age where it seemed like everyone with a beaker and some powder was discovering new stuff, Lavoisier didn't discover a single one. And it wasn't for lack of equipment. He had, like, the best private lab in the world.
Instead, he took other people's discoveries and figured out what they meant. He got rid of the whole "phlogiston" thing, and he figured out what oxygen and hydrogen really were, and he even gave them their names. Basically, he made chemistry more rigorous, clear, and organized.
He and his wife spent years doing, like, really precise experiments. For example, they figured out that when something rusts, it doesn't get lighter, like everyone thought; it gets heavier! It's because it's pulling particles from the air. And that was the first time anyone realized that matter doesn't disappear; it just changes form. If you burn a book, it turns into ash and smoke, but the total amount of matter in the universe stays the same. This is called the conservation of mass, and it was a revolutionary idea. Unfortunately, it happened right around the same time as the French Revolution, and Lavoisier picked the wrong side.
He was part of that hated tax-collecting organization and he helped build that wall around Paris that the revolutionaries hated. In 1791, Marat, who was now a big shot in the government, denounced Lavoisier and said he should be hanged. Marat was later killed in his bathtub by a young woman, but it was too late for Lavoisier.
In 1793, the "Reign of Terror" was in full swing. Marie Antoinette was beheaded and Lavoisier was arrested. The next year, he and 31 other tax collectors were put on trial. Eight of them were acquitted, but Lavoisier and the rest were taken straight to the guillotine. He watched his father-in-law get beheaded, and then he was next. Robespierre, the guy in charge of the Reign of Terror, was executed in the same place, in the same way, just a few months later. And then the Terror ended.
A hundred years later, they put up a statue of Lavoisier in Paris, but then someone pointed out that it didn't even look like him! The sculptor admitted that he had used the head of a mathematician and philosopher, Condorcet, instead. He was hoping no one would notice or care. And they didn't, for, like, 50 years, until World War II. Then, one day, they took it down and melted it for scrap metal. Ouch.
So, then in the early 1800s, it became super popular in England to inhale nitrous oxide, or laughing gas, because it made people feel great. It became a, like, high-class drug for young people. There was even a scientific society that held "laughing gas parties" where people could get high and make fools of themselves for everyone's amusement.
It wasn't until 1846 that someone actually realized that nitrous oxide could be used as an anesthetic! Like, duh! How did nobody think of that before? All those people who suffered unnecessarily during surgery.
This just shows that chemistry in the early 1800s was a bit lost. Part of it was the limitations of the equipment – they didn't even have centrifuges until later in the century. But also, it was a social thing. Chemistry was seen as a science for merchants, for people who worked with coal, potash, and dyes. It wasn't a science for gentlemen. They were more into geology, natural history, and physics. It was different in Europe, but not by much. The most important observation of the century – the discovery of Brownian motion, which is the movement of molecules – wasn't even made by a chemist. It was made by a Scottish botanist named Robert Brown.
Things might have been even worse if it weren't for this guy named Count Rumford. Despite the fancy title, he was just a regular guy named Benjamin Thompson, born in Massachusetts. He was handsome, energetic, ambitious, sometimes brave, and super smart. At 19, he married a rich widow who was 14 years older than him. But when the revolution broke out, he sided with the British and even spied for them. He fled the colonies in 1776, leaving his wife and child behind.
He ended up in Germany and became a military advisor for the Bavarian government. He impressed them so much that they gave him the title "Count Rumford of the Holy Roman Empire." He also designed and built the English Garden in Munich.
And he still found time to do a bunch of science. He became a world-famous expert on thermodynamics and he was the first to explain convection in liquids and ocean currents. He also invented the drip coffee maker, thermal underwear, and a type of stove that's still called the Rumford fireplace. In 1805, he even married Lavoisier's widow! But it didn't work out, and they split up pretty quickly.
Rumford stayed in France until he died in 1814. He was generally respected, except maybe by his ex-wives.
So, the reason I'm talking about him is because he founded the Royal Institution in London. It became, like, the only respected organization that was actively trying to develop chemistry. And that was thanks to a talented young guy named Humphry Davy. Davy became a professor of chemistry at the Royal Institution and quickly became famous as a great lecturer and experimentalist.
Davy started discovering new elements, like potassium, sodium, magnesium, calcium, strontium, and aluminum. He found so many because he figured out how to pass electricity through molten substances, which is now called electrolysis. He discovered 12 elements in total, which was, like, a fifth of all the known elements at the time. Davy could have done even more, but he got addicted to laughing gas. He couldn't get enough of it, and it probably killed him in 1829.
Luckily, there were other people working on chemistry. In 1808, John Dalton came out and said that everything was made up of atoms, and in 1811, this Italian guy with a super operatic name – Lorenzo Romano Amedeo Carlo Avogadro – discovered that equal volumes of any two gases, at the same pressure and temperature, have the same number of atoms. This is called Avogadro's law.
It's amazing for two reasons. First, it laid the foundation for measuring the size and weight of atoms. Eventually, chemists used Avogadro's number to figure out that a typical atom is, like, 0.00000008 centimeters in diameter. Seriously tiny! Second, almost nobody knew about it for, like, 50 years! It's partly because Avogadro was a loner and did all his research by himself. And partly because there weren't many chemistry journals to publish in. Which is kinda weird. The Industrial Revolution was powered by chemistry, but for decades, chemistry barely existed as a formal science.
The Chemical Society of London wasn't founded until 1841, and it didn't start publishing a regular journal until 1848. By that time, most of the other scientific societies in England had been around for at least 20 years. Because of this slow organization, it took until 1860, at the first International Chemical Congress in Karlsruhe, for Avogadro's discovery to really spread.
Because chemists worked in isolation for so long, it took a long time for them to agree on a common language. In the late 1800s, H2O could mean water to one chemist and hydrogen peroxide to another. C2H2 could mean ethylene or methane. There was no standardized way to represent molecules.
Chemists also used all sorts of confusing symbols and abbreviations that they made up themselves. Then J.J. Berzelius in Sweden came up with this system where elements were abbreviated based on their Greek or Latin names. That's why iron is Fe, from the Latin word "ferrum," and silver is Ag, from "argentum."
Berzelius also came up with the idea of using superscripts to show the number of atoms in a molecule, like H2O. Later, for no real reason, people started using subscripts instead, like H2O.
Chemistry was, like, still pretty messy in the late 1800s. So, everyone was happy when this quirky professor from St. Petersburg, Russia, named Dmitri Ivanovich Mendeleev, came along.
Mendeleev was born in Siberia in 1834. He was the youngest in a really big family. His father was a school principal, but he went blind when Dmitri was young, so his mother had to go to work. She managed a successful glass factory. But then a fire destroyed the factory in 1848, and the family was broke. So, his mother took Dmitri on a, like, 6,000-kilometer journey to St. Petersburg so he could get an education. She died soon after.
Mendeleev worked hard and eventually got a job at a university. He was a decent chemist, but he was better known for his messy hair and beard, which he only trimmed once a year.
In 1869, when he was 35, he started thinking about how to arrange the elements. At the time, they were usually arranged either by atomic weight or by their properties, like whether they were metals or gases. Mendeleev's breakthrough was that he realized you could put both on the same table.
Actually, this English guy named John Newlands had proposed something similar three years earlier. Newlands thought that if you arranged the elements by atomic weight, they seemed to repeat certain characteristics every eight places. He called it the "Law of Octaves," comparing it to the octaves on a piano keyboard. People thought it was ridiculous and made fun of him.
At meetings, some people would ask him if he could play them a tune using his elements. Newlands got discouraged and gave up.
Mendeleev used a slightly different approach, grouping the elements in sets of seven, but using the same basic idea. And suddenly, it seemed brilliant. Because the characteristics repeated periodically, it was called the "periodic table."
Mendeleev got the idea from a card game where you arrange cards by suit in rows and by number in columns. He used a similar concept, calling the rows "periods" and the columns "groups." Looking up and down, you could see one set of relationships, and looking left and right, you could see another. Specifically, the columns grouped elements with similar properties. So, copper was above silver, and silver was above gold, because they all had similar chemical affinities as metals. And helium, neon, and argon were in the same column because they were all gases. At the same time, the elements were arranged in rows according to the number of protons in their nucleus, which is called the atomic number.
Hydrogen has one proton, so its atomic number is 1 and it's at the top of the table. Uranium has 92 protons, so its atomic number is 92 and it's near the bottom. As Philip Ball pointed out, chemistry is really just a matter of counting. Atomic weight, on the other hand, is the number of protons plus the number of neutrons.
There was still a lot that people didn't know or understand. The most common element in the universe is hydrogen. And as if we didn't have enough to think about, the second most abundant element – helium – had just been discovered a year earlier. It wasn't even discovered on Earth, but in the sun. It was discovered using a spectroscope during a solar eclipse. That’s why it was named after Helios, the Greek god of the sun. It wasn't isolated until 1895. Chemistry was finally on solid ground thanks to Mendeleev.
For most of us, the periodic table is just this beautiful abstract thing, but for chemists, it made chemistry organized and understandable. It's been called the most beautiful and systematic chart ever devised by humankind.
Today, there are about 120 known elements. Mendeleev only knew of 63. Part of what made him so smart was that he realized that there were more elements out there that hadn't been discovered yet. His periodic table accurately predicted where these new elements would fit once they were found.
Nobody knows how many elements there could be in total, but anything with an atomic weight over 168 is considered "pure speculation." But for sure, any element that is found will neatly fit into Mendeleev's great chart.
There's one last big surprise that came for chemists in the 19th century, starting in 1896. Henri Becquerel in Paris accidentally left a package of uranium salts in a drawer on top of some photographic plates. When he took the plates out, he was surprised to find that the uranium salts had burned an image onto them, as if the plates had been exposed to light. The uranium salts were emitting some kind of radiation.
Given how important this discovery was, Becquerel did something kind of weird. He gave it to a graduate student to investigate. That student was Marie Curie. Curie and her husband, Pierre, discovered that some rocks were constantly emitting huge amounts of energy, without getting smaller or changing in any noticeable way. They couldn't have known – nobody could have known until Einstein explained it – that the rocks were converting mass into energy. Marie Curie called it "radioactivity." They also discovered two new elements: polonium, named after her home country of Poland, and radium.
In 1903, the Curies and Becquerel shared the Nobel Prize in Physics. In 1911, Marie Curie won the Nobel Prize in Chemistry. She's the only person to win both.
Meanwhile, at McGill University in Montreal, a young guy from New Zealand named Ernest Rutherford became interested in the new radioactive materials. He and a colleague named Frederick Soddy discovered that a tiny amount of matter contained a huge amount of energy. He found out that most of the Earth's heat comes from the radioactive decay. They also discovered that radioactive elements decay into other elements. This was true alchemy. Nobody had ever thought that something like that could happen naturally and spontaneously.
Rutherford noticed that the time it took for half of any radioactive material to decay into other elements was always the same. This is known as the half-life, and that constant rate could be used as a clock. By measuring how much radioactivity a substance had and how quickly it was decaying, you could figure out how old it was. He tested a piece of pitchblende – the main ore of uranium – and found that it was 700 million years old. Older than most people thought the Earth was.
In the spring of 1904, Rutherford gave a lecture at the Royal Institution in London. He talked about his theory of radioactive transformation. As part of his lecture, he brought out that piece of pitchblende. Rutherford pointed out that Lord Kelvin had once said that if another source of heat was discovered, his calculations would be overturned. Rutherford had discovered that other source of heat. Thanks to radioactivity, the Earth was probably, no, definitely, much older than Kelvin had calculated.
Kelvin listened to Rutherford's presentation but wasn't convinced. He refused to accept the revised figure and continued to believe that his calculation of the Earth's age was his most important scientific contribution.
Like most scientific revolutions, Rutherford's new discoveries weren't universally welcomed. John Joly in Dublin continued to argue until the 1930s that the Earth was no more than 89 million years old. Others started to worry that Rutherford's new timeline was too long. But even using radioactive dating, it would take decades before science would figure out that the Earth's real age was around 1 billion years. Science was on the right track, but it still had a long way to go.
Kelvin died in 1907, and so did Dmitri Mendeleev. Like Kelvin, his achievements would be remembered, but his later life was, um, not so good. Mendeleev became increasingly eccentric as he got older. He refused to accept radioactivity, electrons, or many other new things. In his final decades, he mostly stormed out of labs and classrooms. In 1955, element 101 was named mendelevium, in his honor. That was appropriate because that too was an unstable element.
Of course, radioactivity was happening all the time. Pierre Curie started to show obvious symptoms of radiation sickness – bone pain, general unwellness – that would only have gotten worse. But we'll never know for sure, because he was killed by a horse-drawn carriage in Paris in 1906.
Marie Curie continued to do great work. In 1914, she helped found the Radium Institute at the University of Paris. Despite winning two Nobel Prizes, she was never elected to the Academy of Sciences. That's largely because, after Pierre died, she had an affair with a married physicist. Even the French thought her behavior was scandalous.
For a long time, people thought that anything with as much energy as radioactivity had to be useful. For years, toothpaste and laxative manufacturers put radioactive thorium in their products. At least until the 1920s, the Glen Springs Hotel in New York proudly advertised the therapeutic effects of its "radioactive mineral springs." But by 1938, it was forbidden to put radioactive materials in consumer products. It was too late for Madame Curie. She died of leukemia in 1934. In fact, radioactivity is so hazardous and lasts for so long that it's still dangerous to handle her papers, even her cookbook. The books in her lab are kept in lead-lined boxes, and you have to wear protective clothing to look at them.
Thanks to the dedication and dangerous work of the first generation of atomic scientists, by the early 20th century, people were realizing that the Earth was super old. Science was about to enter a new age: the atomic age.