Question: Which of the following bonds are polar and which are not C-Se, C-O, Cl-Cl, O=O, N-H, C-H ?

Answer: Polar bonds form between any two dissimilar atoms that have different electronegativity values.

C-Se, C-O, and N-H are polar, while Cl-Cl, O=O, are non-polar because they have identical bonded atoms. C-H is non-polar because the have negligible difference in electronegativity.

Question: Which is the least polar bond: C-Se, C=O, Cl-Br, O=O, N-H, C-H?

Answer: The lower the difference in electronegativity between the bonded atoms, the less polar the bond.

O=O is non-polar; therefore, it is the least polar.

Question: When the difference in electronegativity between the atoms is zero, what do we call the bond?

Answer: Non-polar, or purely covalent. Ex: Br-Br

Question: What do we call the bond If the electronegativity difference between atoms is below 2.0?

Answer: The bond is polar covalent Ex: O-H with O being more electronegative with a negative charge.

Question: What do we call the bond If the electronegativity difference is approximately 2.0 or greater?

Answer: The bond is ionic. Na-Cl