Question 3: (12 marks) Complete the following chart by drawing the Lewis Diagram (1 mark each), the 3D VSEPR Shape (1 mark each) and providing information regarding the shape, angle(s) and molecular polarity (0.5 marks each). Species Lewis Structure 3D VSEPR Sketch Shape Information CHA Electronic shape:_ Molecular shape:_ Bond Angle(s): Polar/Non-Polar?: Electronic shape:_ Molecular shape:_ CO2 Bond Angle(s):

Complete the rest of the table for N, O or X by drawing the number of Lewis structures specified.

Given the bonds C N, C H, C Br, and S O, (a) which atom in each is the more electronegative? (b) which of these bonds is the most polar?

3-105 Consider the structure of Vitamin E shown below, which is found most abundantly in wheat germ oil, sunflower, and safflower oils: (a) Identify the various types of geometries present in each central atom using VSEPR theory. (b) Determine the various relative bond angles as sociated with each central atom using VSEPR theory. (c) Which is the most polar bond in Vitamin E? (d) Would you predict Vitamin E to be polar or nonpolar?

3-89 Is it possible for a molecule to have no polar bonds and yet have a dipole? Explain.

Use the Molecule Shape simulator (http://openstaxcollege.org/I/6MolecShape) to build a molecule. Starting with the central atom, click on the double bond to add one double bond. Then add one single bond and one lone pair. Rotate the molecule to observe the complete geometry. Name the electron group geometry and molecular structure and predict the bond angle. Then click the check boxes at the bottom and right of the simulator to check your answers.

7.30 The bond in HF is said to be polar, with the hydrogen carrying a partial positive charge. For this to be true, the hydrogen atom must have less than one electron around it. Yet the Lewis dot structure of HF attributes two electrons to hydrogen. Draw a picture of the electron density distribution for HF and use it to describe how the hydrogen atom can carry a partial positive charge. How can these two models of the HF bond (the electron density and the Lewis structure) seem so different and yet describe the same thing?

The percent ionic character of a bond can be approximated by the formula 16+3.52 , where is the magnitude of the difference in the electronegativities of the atoms (see Fig. 3.18). Calculate the percent ionic character of HF, HCl, HBr, HI, and CsF, and compare the results with those in Table 3.7.

The connectivity of HNO could be either HNO or HON. Draw a Lewis structure for each and predict which connectivity is the more favorable arrangement.

Question 3: (12 marks) Complete the following chart by drawing the Lewis Diagram (1 mark each), the 3D VSEPR Shape (1 mark each) and providing information regarding the shape, angle(s) and molecular polarity (0.5 marks each). Species Lewis Structure 3D VSEPR Sketch Shape Information CH4 Electronic shape: Molecular shape: Bond Angle(s): Polar/Non-Polar?: Electronic shape:_ CO₂ Molecular shape: Bond Angle(s): Polar/Non-Polar?: Electronic shape: Molecular shape:_ ICIA Bond Angle(s): Polar/Non-Polar?:_ Page 5 of 8