Chemistry · Covalent Bonding: Concept of electronegativity, Fajan's rule, dipole moment, Valence Shell Electron Pair Repulsion (VSEPR) theory and shapes of simple molecules
Calculate the electronegativity of chlorine from bond energy of bond F- \) \) an
Calculate the electronegativity of chlorine from bond energy of \( \boldsymbol{C l}-\boldsymbol{F} \) bond \( \left(61 k c a l m o l^{-1}\right) F- \) \( F\left(38 k c a l m o l^{-1}\right) \) and \( C l-C l \) bond \( \left(58 k c a l m o l^{-1}\right) \) and electronegativity of fluorine \( 4.0 e V \)
- A. 1.42 eV
- B. 1.89 eV
- C. 2.67 eV
- D. 3.22 eV
Step-by-step solution
Using Pauling's electronegativity formula: Δ = D(Cl-F) - [D(Cl-Cl)+D(F-F)]/2 = 61 - (58+38)/2 = 13 kcal/mol. Then |χ_F - χ_Cl| = 0.208√Δ = 0.208√13 ≈ 0.75. Given χ_F = 4.0 eV, χ_Cl = 4.0 - 0.75 = 3.25 eV. The closest option is 3.22 eV.