What is the general formula of an unsaturated hydrocarbon?

1 Answer
Jun 11, 2017

Well, a saturated hydrocarbon has general formula #C_nH_(2n+2)#...

Explanation:

And try it out: methane, #CH_4#; ethane, #C_2H_6#; propane..... Are these species in accord with the formula? What is #n# in each molecule?

Each so-called #"degree of unsaturation"# corresponds to a DOUBLE BOND or a RING-JUNCTION. A 6-membered ring thus has the formula #C_6H_12#, ethylene, an olefin, has the formula #C_2H_4#.

And thus the general formula for olefins or rings is #C_nH_(2n)#.

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