Happy Birthday, Atom

Shipud writes "200 years ago today (Oct. 21) John Dalton revolutionized chemistry by starting the process of turning it into an exact science. He presented the Table of Atomic Weights, at the Manchester literary and Philosophical Society. Dalton's work proposed atoms exist: and not just as an explanatory or philosophical tool. His theory laid the foundations for the periodic table of the elements (1869, Mendeleev), and indeed to all modern chemistry. The molecular weight of compounds is today measured in Daltons, the weight of a hydrogen atom. Read more about Mr. Dalton in today's Nature: a man of many interests, whose atomic theory preceded experimental evidence by a century. Read also about Daltonism -- and why it is named after him."

Comments

Dalton's problems with those atomic models

[azzy]

You know those atomic models we played with at school.. the coloured balls that we attached together with plastic sticks.. making up molecules... Dalton must have had quite a lot of trouble with that if he was colour blind.. so even more kudos for being able to work all that stuff out.. I give him an A+

Only 200 Years?

[Cyno01]

If dalton didn't prove anything and only theorized, didn't Leucippus and Democritus beat him by a few thousand years?

And we're still teaching it wrongly

[devphil]

Even today many schoolrooms have recently-published science books that show a model of the atom that looks like a little solar system, electrons in orbits and all. No mention of quantum/wave dynamics, or the fact that they don't behave anything like orbiting bodies in a solar system.

No, I don't expect 5th graders to learn quantum theory. But just because spherical trigonometry is also too hard for them, I don't expect them to be taught that the earth is flat.

Side note: http://www.intuitor.com/physics_test/index.html is from the same people who brought you the Insultingly Stupid Movie Physics site. See whether you know more about physics than a random chimpanzee!

Re:And we're still teaching it wrongly

[Rasta Prefect]

Even today many schoolrooms have recently-published science books that show a model of the atom that looks like a little solar system, electrons in orbits and all. No mention of quantum/wave dynamics, or the fact that they don't behave anything like orbiting bodies in a solar system.

True, but assuming that they're fifth graders, this provides a handy model for the way things actually work when the point you want to get across is that everything is made of atoms and they share electrons to form molecules. We also teach them Newtons three laws of motion, not mentioning until later "Well this gets all screwed up when you add in gravity and motion". It's an approximation, it's good enough when it's a means to an end. Not everything has to be learned at once.

Re:Ironically

[exp(pi*sqrt(163))]

I think the crucial point is that the atoms themselves aren't the interesting thing and that's why it's not really worth crediting Democritus and Co. The crucial thing that Dalton did was come up with numbers that turn into testable hypotheses.

When any Ancient Greeks argued for the existence of atoms they were saying more about themselves than about the universe. They were revealing that many humans have a problem with the concept of a continuum and prefer everything to be made out of discrete parts. This isn't a property of the universe, it's a property of human minds. If you read Nietzsche then at one point he argues that atomic theory was incorrect even though, at that point, the evidence was stacked against him. I think that what he was actually attacking was this human psychological need to believe in Atomism. In fact Nietzsche supported a quite different vortex theory that you could argue looks more like quantum mechanics. But at the end of the day this is all waffle. What matters are the numbers and that's what Dalton computed.

Re:He proposed, but did not prove

[torved]

Good point about Rutherford, but Dalton should be particularly commended for striving to teach the greatness of the Scientic Method in resolving ideas with reality.

One could say that Rutherford had the "hindsight" of 100 years of Science to help him develop a robust theory of the Atom. I am sure Dalton would have done as well given another 100 years, good eyesight, and a healthy body.

Ironically, Nuclear Physicist Rutherford won his Nobel Prize in Chemistry :)

Atoms

[Anonymous Coward]

"Nothing exists but atoms and the void"

-Democritus, c.400 BC