Some Puns to Brighten the Day

Chemistry is definitely not my favorite class....but I do love puns and chemistry has some good ones along with some other science puns I found:

~I make chemistry puns, periodically.

~Q: Did you hear oxygen went on a date with potassium?
  A: It went OK.

~A photon checks into a hotel and is asked if he needs any help with his luggage. He says, "No, I'm traveling light."

~Q: Why can you never trust atoms?
  A: They make up everything!

~Q: What do you call the leader of a biology gang?
  A: The nucleus.