Diatomic Elements

Seven common elements
A friend by their side     
Diatomic molecules        
Couples bonded tight     

They can make up many things   
Forming different bonds             
And when they get together       
Splitting up is fun                                

Hydrogen ____, & Oxygen ____    
Always hang around                   
Sometimes with a twin - in pairs    
Or as a compound                       

Chlorine _____, Fluorine ___, Bromine ____, too
Then, there's Iodine ____
Hang together in the chart
A nonmetals line

There's one more you might not know
It's called Astatine ____
One that you will never use
When in class with me

Diatomic molecules
Aren't all the same
But the seven up above
You must know by name