Cyclic Alkanes   (Cycloalkanes)  
When does an alkane act like an alkene?
When its cyclic! Some alkanes circle around and join up with themselves. They lose two hydrogens when they join up and so cyclic alkanes have the same general formula as alkenes (CnH2n).

cyclobutane (C4H8

  cyclopropane (C3H6

cyclohexane (C6H12
What would iso-propyl-cyclopentane look like?
The parent ring will be 5 C's and 10 H's. Then pick any of the C's and remove a hydrogen and replace it with an isopropyl group.
       iso-propyl-cyclopentane
 
Cyclic compounds can also have cis and trans configurations because things can stick up or down below the equator of the molecule.
          Go to Organic Cycloalkanes Worksheet