Two scientists walked into a bar. The bartender smiled at them and asked, "Can I get you boys something to drink?" The first scientist wasn't in the mood for anything strong, and he said, "I'll just have a glass of H2O." The bartender looked at the other scientist. "And you?" The man thought for a minute, then said, "I'll have some H2O, too." Their drinks came quickly. The first scientist took a long sip of his water, and sighed contendly. The second scientist took a long sip of is hydrogen peroxide, H2O2, and died.
Sorry if that wasn't that funny xD