I'm not really sure what you are saying, sorry.
There are plenty of different molecules, such as Sucrose, Glucose, etc, which are all forms of carbohydrate molecules.
But when people refer to "carbs", they're not referring to the chemical molecule, but most likely processed carbohydrates such as bread.
Hopefully that's more clear
[1] http://www.ehow.com/about_4613535_chemical-makeup-potato.htm...