Propane (C₃H₈) is a component of liquified petroleum gas. Draw a structural formula for propane. (Hint: Carbon makes four bonds.)

Methylamine (CH₅N) is a gaseous compound with a fishy smell. Draw this molecule using structural formula.

Butane, the fuel used in disposable lighters, has the formula C4H10. The carbon atoms are connected in the sequence C-C-C-C, and each carbon has four covalent bonds. Draw the structural formula of butane.

Isooctane, the substance in gasoline from which the term octane rating derives, has the formula C₈H₁₈. Each carbon has four covalent bonds, and the atoms are connected in the sequence shown. Draw the complete structural formula of isooctane.

The type of formula that shows the arrangements of atoms and bonds is called -