The electronic formulas for methane ethane, and propane are easily written Although the electronic formula representation makes the molecules seem planar, it must be remembered that in all the alkanes the c-c and c-h bonds have the geometrical arrangement set b the tetrahedral configuration of each carbon unIThe electronic formulas for methane, ethane, and propane are easily written. Although the electronic formula representation makes the molecules seem planar, it must be remembered that in all the alkanes the C—C and C—H bonds have the geometrical arrangement set by the tetrahedral configuration of each carbon unit