Question

Among the molecules PF₃ and PCl₃, which molecule exhibits bonds that are more polar?

A) PF₃
B) PCl₃
C) Both have equally polar bonds
D) Neither molecule has polar bonds

Answer 1

PCl₃ exhibits bonds that are more polar than PF₃ due to the greater electronegativity difference between phosphorus and chlorine.

Step-by-step explanation:

The molecule PCl₃ exhibits bonds that are more polar compared to PF₃. This is because the electronegativity difference between phosphorus and chlorine is greater than between phosphorus and fluorine. The greater the electronegativity difference, the more polar the bond.

In PCl₃, the chlorine atom has a greater pull on the shared electrons, resulting in a partial negative charge on the chlorine atom and a partial positive charge on the phosphorus atom. This unequally distributed charge makes the P-Cl bond more polar.

On the other hand, in PF₃, the electronegativity difference between phosphorus and fluorine is lower. The shared electrons in the P-F bond are more evenly distributed, resulting in a smaller difference in charge between the atoms and a less polar bond.