Helium walks into a bar, The bar tender says “We don’t serve noble gasses in here.” Helium doesn’t react. 154
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. 150
Why was the mole of oxygen molecules excited when he walked out of the singles bar? He got Avogadro’s number! 133