Explanation:
Polarity in a bond arises due to the difference in electronegativity between the two atoms involved. The greater the electronegativity difference, the more polar the bond.
* Electronegativity: Electronegativity is a measure of an atom's ability to attract electrons towards itself in a chemical bond. Bromine has a higher electronegativity (2.96) than iodine (2.66).
* Bond Polarity: The electronegativity difference between phosphorus (2.19) and bromine (2.96) is larger than the difference between phosphorus and iodine (2.19 and 2.66).
Therefore, the P-Br bond will be more polar than the P-I bond because the electronegativity difference is greater.
