Trigonal planar molecules have an ideal bond angle of 120° on each side. You can use the Valence Shell Electron Pair Repulsion (VSEPR) Theory to predict the geometry of molecules. If the molecule were perfectly symmetrical, the bond C-O-H bond angle would be 109.5 degrees. The other two angles (H-C=C) are both 121.5°. In this arrangement, the electrons clouds, which repel each other, are as far apart as possible. The H-C-H bond angle is 117°, which is very close to the ideal 120° of a carbon with s p 2 hybridization. With 8 electrons (4 pairs) surrounding the C and O of ethanol, the geometry of the electrons clouds around the C and O are tetrahedral, with bond angles of approximately 109 o. Favorite Answer. Ethanol is tetrahedral around the central oxygen atom.