Write Lewis structures and predict the molecular structures of the following. (See Exercises 105 and 106 .) a. \(\mathrm{OCl}_{2}, \mathrm{KrF}_{2}, \mathrm{BeH}_{2}, \mathrm{SO}_{2}\) b. \(\mathrm{SO}_{3}, \mathrm{NF}_{3}, \mathrm{IF}_{3}\) c. \(\mathrm{CF}_{4}, \mathrm{SeF}_{4}, \mathrm{KrF}_{4}\) d. \(\mathrm{IF}_{5}, \mathrm{AsF}_{5}\) Which of these compounds are polar?

To write the Lewis structures, we need to count the total number of valence electrons for each compound, distribute them around the atoms to satisfy the octet rule (except for exceptions like BeH₂), and identify the central atom. For compounds with an odd electron count, remember that certain elements can have expanded octets.

Using VSEPR Theory, we can predict the molecular structures based on the arrangement of electron groups (bonding and lone pairs) around the central atom. For example, for a compound with AX₂E₃ arrangement (2 bonding and 3 lone pairs), we label the structure as T-shaped.

A compound is polar if there is an imbalance of electron distribution, leading to a net dipole moment. This can be determined by observing the molecular structure and any electronegativity differences between the atoms. Here are the results: a. - OCl₂: (Lewis: O=Cl-Cl) Molecular Structure: Linear, Polar - KrF₂: (Lewis: Kr-Fₓ₂ with 3 lone pairs on Kr) Molecular Structure: Linear, Nonpolar - BeH₂: (Lewis: Be-H-H, Be has 2 valence electrons) Molecular Structure: Linear, Nonpolar - SO₂: (Lewis: S=O-O with 1 lone pair on S) Molecular Structure: Bent, Polar b. - SO₃: (Lewis: S(=O)₃) Molecular Structure: Trigonal planar, Nonpolar - NF₃: (Lewis: N-Fₓ₃ with 1 lone pair on N) Molecular Structure: Trigonal pyramidal, Polar - IF₃: (Lewis: I-Fₓ₃ with 2 lone pairs on I) Molecular Structure: T-shaped, Polar c. - CF₄: (Lewis: C-Fₓ₄) Molecular Structure: Tetrahedral, Nonpolar - SeF₄: (Lewis: Se-Fₓ₄ with 1 lone pair on Se) Molecular Structure: Seesaw, Polar - KrF₄: (Lewis: Kr-Fₓ₄ with 2 lone pairs on Kr) Molecular Structure: Square planar, Nonpolar d. - IF₅: (Lewis: I-Fₓ₅ with 1 lone pair on I) Molecular Structure: Square pyramidal, Polar - AsF₅: (Lewis: As-Fₓ₅) Molecular Structure: Trigonal bipyramidal, Nonpolar Polar compounds are: OCl₂, SO₂, NF₃, IF₃, SeF₄, and IF₅.