1. Give the electron configuration for the following atoms or ions:
Fe, Fe^{2+}, Cu, Cu^{+}.

Fe [Ar]4s

^{2}3d^{6}Fe

^{2+}[Ar]3d^{6}Cu [Ar]4s

^{1}3d^{10}Cu

^{+}[Ar]3d^{10}

2. Draw the lowest energy Lewis dot structures for each of the following and give the formal charge and the oxidation number for each atom in the molecule: a) SO_{3}; b) XeO_{3}; c) BrF_{3}; d) IF_{5}.

a) SO

_{3}formal charges: S = 0, O = 0; oxidation numbers: S = +6, O = –2b) XeO

_{3}formal charges: Xe = 0, O = 0; oxidation numbers: Xe = +6, O = –2c) BrF

_{3}formal charges: Br = 0, F = 0; oxidation numbers: Br = +3, F = –1d) IF

_{5}formal charges: I = 0, F = 0; oxidation numbers: I = +5, F = –1

3. Draw the structures of each of the molecules in question 2 and estimate all of the bond angles in each.

a) SO

_{3}trigonal planar, all O-S-O angles = 120°b) XeO

_{3}pyramidal, all O-Xe-O angles ~ 108° (slightly less than the perfect tetrahedral angle)c) BrF

_{3}bent T-shaped, two F-Br-F angles ~ 89° and one F-Br-F angles ~ 179°d) IF

_{5}square-based pyramid, two F-Br-F angles ~ 89° and one F-Br-F angles ~ 179°

4. Give the point group for each molecule in question 2.

a) SO

_{3}D_{3h}b) XeO

_{3}C_{3v}c) BrF

_{3}C_{2v}d) IF

_{5}C_{4v}