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

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

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.