Isoalkanes are saturated, branched-chain hydrocarbons with the formula CnH2n+2. They contain carbon atoms in the sp3 hybridization state. These substances differ from alkanes in certain physical properties, such as melting point, and should not be confused, by formula, with them. Rules: The largest chain is chosen and numbered both ways. The radicals and their order are indicated, listed alphabetically. The name in which the sum of the digits is the smallest is then chosen.