a. The most polar bond?
b. The least polar bond?
NaI
LiBr
Cl2
KCl
The Correct Answer and Explanation is :
To determine which bond is the most and least polar among the given compounds (NaI, LiBr, Cl2, and KCl), we must consider the electronegativity difference between the atoms involved in the bond. Electronegativity refers to an atom’s ability to attract and hold onto electrons in a bond. The greater the electronegativity difference between two atoms, the more polar the bond will be.
a. The most polar bond
The most polar bond will be between two atoms with a large electronegativity difference. Let’s evaluate the electronegativity values of the elements involved in each bond:
- NaI (Sodium Iodide): Sodium (Na) has an electronegativity of 0.93, and iodine (I) has an electronegativity of 2.66. The electronegativity difference is 2.66 – 0.93 = 1.73.
- LiBr (Lithium Bromide): Lithium (Li) has an electronegativity of 0.98, and bromine (Br) has an electronegativity of 2.96. The electronegativity difference is 2.96 – 0.98 = 1.98.
- Cl2 (Chlorine molecule): Both atoms are chlorine, so the electronegativity difference is 0, meaning no polarity.
- KCl (Potassium Chloride): Potassium (K) has an electronegativity of 0.82, and chlorine (Cl) has an electronegativity of 3.16. The electronegativity difference is 3.16 – 0.82 = 2.34.
The most polar bond is found in KCl (Potassium Chloride) because the electronegativity difference between potassium and chlorine (2.34) is the largest among the compounds listed.
b. The least polar bond
The least polar bond occurs when the electronegativity difference is the smallest. In this case, Cl2 (Chlorine molecule) has the least polar bond because both atoms involved are chlorine, meaning the electronegativity difference is 0. Since there is no difference in electronegativity, the bond in Cl2 is nonpolar.
Conclusion:
- The most polar bond is in KCl.
- The least polar bond is in Cl2.
This is because the greater the electronegativity difference between the atoms, the more polar the bond, and a zero difference results in no polarity at all.