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CHCl3 Lewis Structure

Chloroform (trichloromethane) · A solvent and former anaesthetic.

Lewis structure of CHCl3 (Chloroform)The atoms around the centre are not all the same, so the bond dipoles are different sizes and cannot cancel.CClClClH

The CHCl3 Lewis structure has 26 valence electrons, drawn as three C–Cl bonds and one bond to hydrogen, with nine lone pairs in total. The central C is sp3 hybridized, which makes it a tetrahedral molecule with a bond angle of 109.5 degrees. CHCl3 is polar: the atoms around the centre are not all the same, so the bond dipoles are different sizes and cannot cancel.

Calculated properties

Calculated properties of CHCl3
Total valence electrons 26
Bonding electrons 8 (4 shared pairs)
Nonbonding electrons 18 (9 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 polar
Formal charges all zero
Resonance structures none
Molar mass 119.369 g/mol

How to draw the CHCl3 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.

    4 (C) + 1 (H) + 3 x 7 (Cl) = 26 valence electrons

  2. Choose the central atom

    Carbon is the central atom - it forms four bonds and is never terminal in these molecules.

  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.

    4 bonds x 2 = 8 electrons used, 18 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 18, has 18, exactly enough

  5. Fill in the lone pairs

    Every electron not in a bond sits as a lone pair on an atom. Each atom takes exactly what it needs to finish its shell - there is no choice left at this point.

    Cl1: 3, Cl2: 3, Cl3: 3 (18 electrons)

  6. Check the central atom

    C ends up with a full octet. Every electron in the budget is now placed.

    C: 8 bonding + 0 nonbonding = 8

  7. 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

  8. 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

  9. Decide whether it is polar

    The atoms around the centre are not all the same, so the bond dipoles are different sizes and cannot cancel.

    dipoles do not cancel -> polar

Is CHCl3 polar or nonpolar?

CHCl3 is polar. The atoms around the centre are not all the same, so the bond dipoles are different sizes and cannot cancel.

BondElectronegativity differenceCharacter
C–Cl 0.61 polar covalent
C–H 0.35 nonpolar covalent
Why this molecule gets set as a problem: Break the symmetry of CCl4 by one atom and the dipoles stop cancelling.

Common questions

How many valence electrons does CHCl3 have?

CHCl3 has 26 valence electrons. 8 of them are in bonds and 18 sit in lone pairs.

What is the molecular geometry of CHCl3?

CHCl3 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 CHCl3?

The bond angle in CHCl3 is 109.5 degrees. That is the ideal tetrahedral angle, and nothing distorts it here.

What is the hybridization of CHCl3?

The central C in CHCl3 is sp3 hybridized. Steric number 4 means 4 orbitals have to be mixed, which is exactly what sp3 gives you.

Is CHCl3 polar or nonpolar?

CHCl3 is polar. The atoms around the centre are not all the same, so the bond dipoles are different sizes and cannot cancel.

How this page was produced. The formula was parsed, the connectivity resolved (central atom), 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.