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C2H4 Lewis Structure

Ethylene (ethene) · The plant hormone that ripens fruit, and the feedstock for polyethylene.

Lewis structure of C2H4 (Ethylene)The bond dipoles and lone pairs are arranged symmetrically, so the vectors cancel and the molecule has no net dipole.CCHHHH

The C2H4 Lewis structure has 12 valence electrons, drawn as one C=C bond and four bonds to hydrogen, with zero lone pairs in total. The central C is sp2 hybridized, which makes it a trigonal planar molecule with a bond angle of 120 degrees. C2H4 is nonpolar: the bond dipoles and lone pairs are arranged symmetrically, so the vectors cancel and the molecule has no net dipole.

Calculated properties

Calculated properties of C2H4
Total valence electrons 12
Bonding electrons 12 (6 shared pairs)
Nonbonding electrons 0 (0 lone pairs)
Lone pairs on C 0
Electron domains (steric number) 3
VSEPR notation AX3
Electron geometry trigonal planar
Molecular geometry trigonal planar
Bond angle 120°
Hybridization sp2
Polarity nonpolar
Formal charges all zero
Resonance structures none
Molar mass 28.054 g/mol

How to draw the C2H4 Lewis structure

  1. 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) + 4 x 1 (H) = 12 valence electrons

  2. Work out what is bonded to what

    The two C atoms bond to each other and split the hydrogens evenly between them.

  3. 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.

    5 bonds x 2 = 10 electrons used, 2 left

  4. 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 4, has 2, short by 2

  5. Turn the shortfall into multiple bonds

    Being short means atoms have to share more. Every pair that moves from a lone pair into a bond counts twice - once for each atom - so a shortfall of 2 is covered by 1 extra shared pair. That is where the double bond comes from.

    C1=C2

  6. 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

  7. Work out the shape

    Count the electron domains on C: 3 bonded groups. A double or triple bond still counts as one domain, because it points in one direction. That gives trigonal planar electron geometry; ignore the lone pairs and the atoms themselves sit in a trigonal planar arrangement.

    steric number 3 -> sp2 -> trigonal planar, bond angle 120

  8. 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 C2H4 polar or nonpolar?

C2H4 is nonpolar. The bond dipoles and lone pairs are arranged symmetrically, so the vectors cancel and the molecule has no net dipole.

BondElectronegativity differenceCharacter
C–H 0.35 nonpolar covalent
C–C 0.00 nonpolar covalent
Why this molecule gets set as a problem: A flat molecule: sp2 carbons hold everything in one plane.

Common questions

How many valence electrons does C2H4 have?

C2H4 has 12 valence electrons. 12 of them are in bonds and 0 sit in lone pairs.

What is the molecular geometry of C2H4?

C2H4 is a trigonal planar molecule. The central C has 3 bonded groups, a steric number of 3, which gives trigonal planar electron geometry and a trigonal planar molecule.

What is the bond angle in C2H4?

The bond angle in C2H4 is 120 degrees. That is the ideal trigonal planar angle, and nothing distorts it here.

What is the hybridization of C2H4?

The central C in C2H4 is sp2 hybridized. Steric number 3 means 3 orbitals have to be mixed, which is exactly what sp2 gives you.

Is C2H4 polar or nonpolar?

C2H4 is nonpolar. The bond dipoles and lone pairs are arranged symmetrically, so the vectors cancel and the molecule has no net dipole.

How this page was produced. The formula was parsed, the connectivity resolved (symmetric dimer), and every bond-order arrangement enumerated and scored on octet satisfaction, formal charge and where that charge sits. The structure above is the winner. Bond angles, hybridization and the polarity verdict are read off the resulting geometry, not looked up.