Re: How can I prove that oxygen is vital to rusting?

Richard,
You problem is a very easy one to prove.  To do this experiment, you will 
need 2 jars, 2 shiny nails, 2 sponges or wet rags and a helium-filled 
balloon.  The first part is pretty simple.  Put a wet sponge or rag in the 
bottom of the first jar, lay one of the shiny nails on the rag and seal 
the jar.  The second jar is a little tricky but put the wet rag and shiny 
nail in the bottom of the jar and invert it.  Take the helium balloon and 
untie it and hold the second jar upside down (this is the tricky part 
becasue you need to keep the sponge and nail inside the jar as well).  
Stick the open end of the ballon in the jar and let the helium leak into 
the jar.  Since helium is lighter than air, it will fill the jar from the 
top to the bottom and displace the air, along with the oxygen.  While the 
jar is still upside-down, screw the lid on tightly and turn it back over.  
In a few hours or days, you will notice the nail that is in the air will 
have begun to rust.  If you got the helium in the second jar, it will 
still be shiny.  Since you removed the oxygen from the second jar, rusting 
cannot occur.  Hope this helps.

Carlin Gregory