C2H6 Lewis Structure
Ethane · The second component of natural gas, cracked industrially into ethylene.
The C2H6 Lewis structure has 14 valence electrons, drawn as one C–C bond and six bonds to hydrogen, with zero lone pairs in total. The central C is sp3 hybridized, which makes it a tetrahedral molecule with a bond angle of 109.5 degrees. C2H6 is nonpolar: the bond dipoles and lone pairs are arranged symmetrically, so the vectors cancel and the molecule has no net dipole.
- 14 valence e−
- tetrahedral
- 109.5° bond angle
- sp3
- nonpolar
Calculated properties
| Total valence electrons | 14 |
|---|---|
| Bonding electrons | 14 (7 shared pairs) |
| Nonbonding electrons | 0 (0 lone pairs) |
| Lone pairs on C | 0 |
| Electron domains (steric number) | 4 |
| VSEPR notation | AX4 |
| Electron geometry | tetrahedral |
| Molecular geometry | tetrahedral |
| Bond angle | 109.5° |
| Hybridization | sp3 |
| Polarity | nonpolar |
| Formal charges | all zero |
| Resonance structures | none |
| Molar mass | 30.07 g/mol |
How to draw the C2H6 Lewis structure
Step through it. The bar shows how much of the 14-electron budget is spent at each stage - it never grows, which is the whole constraint.
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Skeleton. Join every connected pair with one bond. 7 bonds spends 14 electrons.
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Outer octets. Spend electrons as lone pairs on the outer atoms. That uses the entire budget, and the central atom has nothing left over.
The reasoning at each step
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Count the valence electrons
Add up the outer-shell electrons every atom brings. That total is the budget for the whole structure - every line and every dot has to come out of it, and nothing may be added.
2 x 4 (C) + 6 x 1 (H) = 14 valence electrons -
Work out what is bonded to what
The two C atoms bond to each other and split the hydrogens evenly between them.
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Join everything with single bonds first
Every connection starts as one shared pair. Draw them all before worrying about double bonds - the arithmetic in the next step is what tells you where the double bonds have to go.
7 bonds x 2 = 14 electrons used, 0 left -
Work out how far short you are
Add up what every atom still needs to fill its shell - eight electrons for most atoms, two for hydrogen - minus what its single bonds already give it. Compare that with the electrons you have left. The difference decides everything that follows.
needs 0, has 0, exactly enough -
Check the formal charges
Formal charge is valence electrons, minus lone-pair electrons, minus the number of bonds. Every atom here comes out at zero, which is the sign of a good structure.
all formal charges = 0 -
Work out the shape
Count the electron domains on C: 4 bonded groups. A double or triple bond still counts as one domain, because it points in one direction. That gives tetrahedral electron geometry; ignore the lone pairs and the atoms themselves sit in a tetrahedral arrangement.
steric number 4 -> sp3 -> tetrahedral, bond angle 109.5 -
Decide whether it is polar
The bond dipoles and lone pairs are arranged symmetrically, so the vectors cancel and the molecule has no net dipole.
dipoles cancel -> nonpolar
Is C2H6 polar or nonpolar?
C2H6 is nonpolar. The bond dipoles and lone pairs are arranged symmetrically, so the vectors cancel and the molecule has no net dipole.
| Bond | Electronegativity difference | Character |
|---|---|---|
| C–H | 0.35 | nonpolar covalent |
| C–C | 0.00 | nonpolar covalent |
Common questions
How many valence electrons does C2H6 have?
C2H6 has 14 valence electrons. 14 of them are in bonds and 0 sit in lone pairs.
What is the molecular geometry of C2H6?
C2H6 is a tetrahedral molecule. The central C has 4 bonded groups, a steric number of 4, which gives tetrahedral electron geometry and a tetrahedral molecule.
What is the bond angle in C2H6?
The bond angle in C2H6 is 109.5 degrees. That is the ideal tetrahedral angle, and nothing distorts it here.
What is the hybridization of C2H6?
The central C in C2H6 is sp3 hybridized. Steric number 4 means 4 orbitals have to be mixed, which is exactly what sp3 gives you.
Is C2H6 polar or nonpolar?
C2H6 is nonpolar. The bond dipoles and lone pairs are arranged symmetrically, so the vectors cancel and the molecule has no net dipole.