[chrisso80b]

Hey all,
Im having some trouble with double bond equivalents, I understand the equation:
DBE= C- H/2 - X/2 + N/2 + 1
and I understand how to apply it to a molecule e.g. for C6H6 the DBE= 4

My question is, what does DBE tell me?? What does the 4 represent? Does it mean, there are 4 molecules with the chemical formula C6H6? Or does it mean there are 4 double bonds in the molecule?
Thanks!

[enahs]

This is also called the Index Of Hydrogen Deficiency.
It is defined as the number of pairs of hydrogen's that must be subtracted from the molecular formula of the corresponding alkane to give the molecular formula of the compound under consideration.
 
It is sometimes called the degree of unsaturation.

So in your example you have C6. The Hexane is C₆H₁₄. You have to subtract 4 pairs of hydrogens (8 hydrogen atoms total) to get to C6H6.

It tells you other stuff, but that is a quick tutorial.

[chrisso80b]

Ohhh ok i see! Thanks a lot!