Since ancient Greek times, philosophers and scientists have pondered the atom. For a couple thousand years, humans could only speculate on the structure and other properties of the smallest unit of matter. It wasn't until the 1980s that chemists saw individual atoms.
Bestselling author Sam Kean takes us through the nearly 2,400-year quest to see the atom in a new episode of the Reactions sub-series, "Legends of Chemistry."
Check out the video here:
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