MOLECULAR POLARITYFIELD NOTE 172 / 175
Is Trimethylamine (C3H9N) polar or nonpolar?
Trimethylamine (C3H9N) is polar because its three C–N bonds point around a pyramidal nitrogen rather than canceling in one plane.
Trimethylamine · tetrahedral at C; pyramidal at N
The molecule in space
Drag to turn the molecule. Show angles to read the model geometry.
01 / MODEL RECORDPubChem 3D coordinates. Atom sizes and bond thickness are illustrative.How model data is used ↗
Why C3H9N is polar
Nitrogen in (CH3)3N has three C–N single bonds and one lone pair. The three methyl groups sit around a pyramidal nitrogen center, so their bond dipoles have a net component along the pyramid axis.
What to notice
If nitrogen were flat with three equal C–N bonds, in-plane dipoles could cancel. Its lone pair makes the actual local geometry pyramidal and leaves a nonzero dipole.
Common questions about C3H9N
- 01
What does the Lewis structure of C3H9N show?
Nitrogen makes one single bond to each of three CH3 groups and keeps one lone pair. Each carbon has three C–H bonds plus one C–N bond.
- 02
What is the molecular geometry of C3H9N?
C3H9N has a tetrahedral at C; pyramidal at N molecular geometry. The 3D model shows representative bond angles of 110.5° and 112.3°. These angles come from the displayed model coordinates.
- 03
What is the molar mass of C3H9N?
C3H9N has an approximate molar mass of 59.11 g/mol, calculated from its formula using abridged standard atomic weights. Natural isotope variation can change the last digits.