Electrometallurgy, the science of producing metals from metallic ores through the use of electricity. It deals with both the use of electricity for various heating processes and the use of electricity to produce chemical changes (a process called electrolysis).
Mass spectrometry enables the major league to sniff out athletes guilty of doping. It can also help us locate oil or design a killer perfume. Who says chemistry isn't cool?
That's one seriously big number, and technically Amedeo Avogadro didn't even come up with it. So how did the Italian chemist make such an indelible (numerical) mark on the wonderful world of chemistry?