Question

g Where, approximately, is the negative pole on each of these molecules? Lewis structure for C O F 2. A central C atom is single bonded to two F atoms and double bonded to one O atom. There are two lone pairs of electrons on the O atom and three lone pairs of electrons on each F atom. towards the O atom toward one of the F atoms between the F atoms The Lewis structure for C O F H. A central C atom is single bonded to an H and F atom and double bonded to an O atom. There are two lone pairs of electrons on the oxygen atom and three lone pairs of electrons on the F atom. between the F and H atoms towards the O atom between the O and F atoms Which molecule should have the higher dipole moment, and why? COF2 because it contains more lone pairs. COF2 because it contains more F atoms. COFH because the polar bonds in COF2 nearly cancel each other out.

Answer 1

Answer:

1. For $COF_{2}$: between the F atoms. For COFH: between the O and F atoms.

2. COFH because the polar bonds in $COF_{2}$ nearly cancel each other out.

Explanation:

1. In the compound $COF_{2}$, there are two sets of bonds such as the C=O and C-F bonds. If we consider the electronegativities of the two bonds, the electronegativity of the C-F bond is slightly higher than that of the C=O. Thus, the negative pole exists in the middle of the two fluorine atoms Similarly, in the compound COFH, there are three sets of bonds which are C=O, C-H, and C-F. The negative pole exits in the middle of oxygen and fluorine.

2. The compound COFH has the highest dipole moment because than $COF_{2}$ because the bonds in $COF_{2}$ neutralize each other.

Answer 2

The molecule with higher dipole moment is COFH because the geometry of the molecule in the COF2 nearly cancel the dipolar moment of each other. To be more clear:

The dipolar moment is the vectorial sum of all bond moments in the molecule or dipolar moment of each bond. The dipolar moment of a molecule with three or more atoms is determined by bond polarity as their geometry.

COF2 has a trigonal planar structure which are symmetric. The electronegativity of oxygen is slightly different regarding fluor. So as you can see in the image, the electronic density is specially displaced to the fluor atoms, but either to the oxygen atom.

COFH has a trigonal structure but differs from COF2 because there is an hydrogen who is donating it's electronic density, so in this zone the electronic density is less than over oxygen or fluor. That makes bond angles be different between them.