Here is a puff or two of breath(s) of fresh air for you all given the pollution we are suffering:

What do you call it when Oxygen and Nitrogen train at the gym together?  
Air conditioning:

I asked my wife if she would get "Nitrogen" or "Dioxide" tattooed on her backside. 
She said NO2 both:

 

I was in class one day and my my teacher asked me a question
Teacher: can you give me the chemical formula for nitrogen monoxide?
Me: NO

 

 

8 hours ago, ballpoint said:

Duh!!

A man, somewhat drunk, goes into a bar and says to the bar tender “I bet you I can bite my left eye.” The bartender takes the bet, to which the man takes out his glass eye and bites it. The bartender pays up.

The next day the man comes back, again somewhat drunk, and says to the bartender “I bet you I can bite my right eye.” Thinking that surely the man can’t have two glass eyes the bartender takes the bet, to which the man takes out his dentures, and uses them to bit his eye. The bar tender pays up.

The next day the man appears again, and this time he is super drunk, he approaches the bartender and says “Put a shot glass down the far end of the bar, and I’ll stay at this end and <deleted> into it, if I miss; I’ll pay you double the bet of the last two days.’ The bartender agrees, and the man straight out pisses al over the bar. “The bartender says “Well I guess I won, but you don’t look too upset about losing.” The man explains ‘Well you see; I bet this other guy that I could <deleted> all over your bar, and you wouldn’t care.”