Nº de atomos de C                        formula molecular                     Nº teorico de isomeros

4                                                    C₄H₁₀                                                          2

5                                                     C₅H₁₂                                                         3

6                                                     C₆H₁₄                                                         5

7                                                     C₇H₁₆                                                         9

8                                                     C₈H₁₈                                                        18