Two hydrogen atoms walk into a bar. One says, "I think I've lost an electron." The other says, "Are you sure?" The first says, "Yes, I'm positive..."

 797

0  

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."

 2256

3  

As an ion chromatography chemist I made this one up: Anions aren't negative, they're just misunderstood.

 1896

1  

An instructor in chemical warfare asked soldiers in his class: "Anyone knows the formula for water?" "Sure. That's easy," said one man. "What is it?" "H, I, J, K, L, M, N, O." "What, what?" reasked the instructor. "H to O," explained the chemistry expert.

 814

1  

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!"

 1197

0