1 List the intermolecular and intramolecular forces. Why is the term intramolecular sometimes a misnomer? Identify intramolecular and intermolecular forces for each of the following. Predict the order in which they would melt. GeH4 SiH4 SnH4 CH4

2 A. Identify intramolecular and intermolecular forces for each of the following. The electronegativities of Se, S, and Te are all within 0.5 of each other which is quite small. Predict the order in which they would melt. When these substances melt, are intermolecular or intramolecular forces being broken? H2Te H2S H2O H2Se B. If a mixture contained all four of these substances in the liquid phase, which would be the first to distill? Which would be the last? How does this list compare with your list in part A? Why?

3 Does the following diagram best describe a crystalline solid, liquid, or gas? Explain.

4 The following are in order; do they go in order of increasing or decreasing melting points? Use intramolecular and intermolecular forces to thoroughly justify the order. C, BaCl2, HF, CO, Ne, H2 What type of solid would each substance form? Are any solid types not represented? If so, list them and give an example.

5 Which of the following molecules can form hydrogen bonds with other molecules of the same kind? Draw two molecules for each selection and indicate Hydrogen bonding. Circle covalently-bonded hydrogens that cannot H-bond. CH3F CH3NH2 CH3OH CH3Br

6 As the intermolecular attractive forces between molecules increase in magnitude, do you expect each of the following to increase or decrease in magnitude? boiling point, melting point, viscosity, surface tension, adhesion, cohesion, vapor pressure

7 What kinds of attractive forces exist between particles in molecular solids, network solids, ionic solids, and metallic solids (discuss electrons)? A white substance melts with some decomposition at 730°C. As a solid, it is a nonconductor of electricity, but it dissolves in water to form a conducting solution. Which type of solid might the substance be? How do you know?

8 The state of aggregation of solids can be described as belonging to the following four types: (1) ionic (3) network (2) metallic (4) molecular For each of these types of solids, sketch a diagram of the solid and indicate the kinds of particles that occupy the lattice points and identify forces among these particles. How could each type of solid be identified in the laboratory?

9 Identify the type of solid the representation below depicts. List all the properties of this solid type that you know. Use features of the diagram to explain why this solid has two properties you listed.

10 For practice: For the following: draw the lewis structure (with formal charges), name the shape according to modern bonding theory, identify angles, and indicate polarity and hybridization. Explain similarities and differences: phosphite and phosphate