# How can I write the Lewis dot structure for C2H6?

Jan 11, 2015

The first step in drawing the Lewis dot structure for ethane (${C}_{2} {H}_{6}$) is to determine how many valence electrons are available for the molecule.

Since $C$ has 4 valence electrons, and each $H$ atoms contributes 1 valence electron, the total number of electrons will be

$2 \cdot 4 + 6 \cdot 1 = 14$ ${\text{e}}^{-}$

This means that the Lewis dot structure for ${C}_{2} {H}_{6}$ must account for 14 valence electrons, either through bonding between atoms, or through lone pairs.

So, the two $C$ atoms are placed in the center of the molecule. Each $C$ atom forms three covalent bonds with three $H$ atoms, with one aditional covalent bond being formed between the two $C$ atoms.

Each of these seven single bonds contains 2 electrons, which means that a total of

$7 \cdot 2 = 14$ ${\text{e}}^{-}$ were used for the ${C}_{2} {H}_{6}$ molecule.