If you're not part of the solution, you're part of the precipitate.
Q: What did the scientist say when he found 2 isotopes of helium? A: HeHe
Q: What do you do with a sick chemist? A: If you can't helium, and you can't curium, then you might as well barium.
Q: Anyone know any jokes about sodium? A: Na
A small piece of sodium that lived in a test tube fell in love with a Bunsen burner. "Oh Bunsen, my flame," the sodium pined. "I melt whenever I see you," The Bunsen burner replied, "It's just a phase you're going through."
Helium walks into a bar. The bartender says "We don't serve noble gasses in here." Helium doesn't react.
A proton and a neutron are walking down the street. The proton says, "Wait, I dropped an electron help me look for it." The neutron says "Are you sure?" The proton replies "I'm positive."
Two chemists go into a restaurant. The first one says "I think I'll have an H2O." The second one says "I think I'll have an H2O too" - and he died.
Q: What is the chemical formula for "banana"? A: BaNa2
A biologist, a chemist and a statistician are out hunting. The biologist shoots at a deer and misses 5th to the left. The chemist takes a shot and misses 5th to the right. The statistician yells "We got 'em!"