A Little Chemistry Help Please?

Question

I don't understand why H2CO is considered Trigonal Planar. I get that it has 3 atoms attached to the central carbon, but aren't there two lone pairs of electrons on the oxygen? I thought if it's trigonal planar you can't have any lone pairs, no? Thanks to anyone who can help :)

Answer 1

The structrure is

H - C = O

.....H

the geometry is determined by repulsion among the pairs of electrons associated with CENTRAL atom. In our case C ( not oxigen)

Only valence electrons of the central atom influence the molecular shape