Question

methylcyclohexane formula?

Answer 1

to find formulas from molecular compounds there a few things you have to look at

the last part is always the main chain, the suffix
-ane, is for an alkane (meaning only single bonds)
-ene, for alkene (double bond)
-yne- alkyne (triple bond)

propane as alkane,
eg 1 double bond: propene
if you have 2 double/triple bond, you include di- prefix
eg. propadiene

the part in front are the side groups, methyl CH3