MOLECULAR POLARITYFIELD NOTE 71 / 175
Is CH2O polar or nonpolar?
CH2O is polar because its strong C=O bond dipole is not canceled by the two C–H bonds in its planar structure.
Formaldehyde · trigonal planar
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 CH2O is polar
Formaldehyde has a trigonal planar geometry with a central carbon double-bonded to oxygen and single-bonded to two hydrogens. Oxygen (3.44) is much more electronegative than carbon (2.55), creating a strong C=O bond dipole.
What to notice
Formaldehyde is planar, yet it is polar: the C=O bond is unlike the two C–H bonds, so their contributions cannot balance it.
Common questions about CH2O
- 01
What does the Lewis structure of CH2O show?
The common Lewis structure is H2C=O: carbon has two C–H single bonds and a C=O double bond. O has two lone pairs.
- 02
What is the molecular geometry of CH2O?
CH2O has a trigonal planar molecular geometry. The 3D model shows representative bond angles of 122.2° and 115.5°. These angles come from the displayed model coordinates.
- 03
What is the molar mass of CH2O?
CH2O has an approximate molar mass of 30.03 g/mol, calculated from its formula using abridged standard atomic weights. Natural isotope variation can change the last digits.