Lewis structure of CHCl₃
26 valence electrons. One C-H single bond and three C-Cl single bonds, with no lone pair on C.
Lewis structure
26 valence electronsFormal charges: none
Why this shape
- C has 4 valence electrons. It uses four in one single bond to H and three single bonds to Cl, so none are left over.
- Steric number = four sigma bonds + no lone pairs = 4, so C is sp³ hybridised.
- Four electron pairs point to the corners of a tetrahedron (tetrahedral electron geometry). With no lone pairs the atoms take the same shape: tetrahedral.
- There is no lone pair, but one bond is C-H and three are C-Cl, so the angles are close to 109.5 degrees but not all equal.
- The bond dipoles do not cancel in the tetrahedral shape, so CHCl₃ is polar.
How to draw it
- Count the valence electrons: C 4 + H 1 + 3 × Cl 7 = 26 valence electrons, 13 pairs.
- Put C in the middle and join it to the four outer atoms with single bonds.
- Give each outer atom lone pairs until it has an octet (H needs only two electrons), then put any electrons left over on the central atom.
- Result: one C-H single bond and three C-Cl single bonds, with no lone pair on C.
- Formal charge = valence electrons − lone pair electrons − number of bonds. Here: none.
Class 11, Chapter 4 Chemical Bonding and Molecular Structure.
Lewis structure of CHCl3: quick answers
How many valence electrons are in CHCl3?
C 4 + H 1 + 3 × Cl 7 = 26 valence electrons, 13 pairs.
What are the formal charges in the Lewis structure of CHCl3?
Every atom has a formal charge of zero.
How many lone pairs are in the Lewis structure of CHCl3?
9 in all, none on the central C.