Chemistry Bonding Assignment

Chemistry 30
Chemical Bonding – Properties of Molecules

1. For the following molecules determine which atoms are bonded (write the symbols with a bond between them), the electronegativity difference between them, and the type of chemical bond it represents. If the bond is ionic, state what ions are produced. If the bond is polar covalent, indicate the direction of the dipole on the symbols from the first part.

a) KCl Electronegativity difference = K - Cl = 0.8 - 3.0 = 2.2 ionic bond K1+ Cl1- b) LiBr Electronegativity difference = Li - Br = 1.0 - 2.8 = 1.8 ionic bond Li1+ Br1- [pic] c) HI Electronegativity difference = H - I = 2.1 - 2.5 = 0.4 polar covalent bond [pic] d) CF4 Electronegativity difference = C - F = 2.5 - 4.0 = 1.5 polar covalent bond [pic] e) CaS Electronegativity difference = Ca - S = 1.0 - 2.5 = 1.5 polar covalent bond [pic] f) H2Se Electronegativity difference = H - Se = 2.1 - 2.4 = 0.3 polar covalent bond [pic] g) SiCl4 Electronegativity difference = Si - Cl = 1.8 - 3.0 = 1.2 polar covalent bond h) P4 Electronegativity difference = P - P = 2.1 - 2.1 = 0.0 covalent bond [pic] i) FeCl3 Electronegativity difference = Fe - Cl = 1.8 - 3.0 = 1.2 polar covalent bond j) BrCl7 Electronegativity difference = Br - Cl = 2.8 - 3.0 = 0.2 covalent bond k) CS2 Electronegativity difference = C - S = 2.5 - 2.5 = 0.0 covalent bond l) K2S Electronegativity difference = K - S = 0.8 - 2.5 = 1.7 ionic bond K1+ S2-

2. For c, d, f, g, and k from question 1 determine whether the molecules are polar, or nonpolar. Show all work. [pic] c) HI Electronegativity difference = H - I = 2.1 - 2.5 = 0.4 polar covalent bond