CHEM133 Week 13 Lesson 6 Quiz

1. Question: We discussed the different types of intermolecular forces in this lesson. Which is the strongest in CF2H2 ? 2. Question: Water is such a special molecule with some really unique properties. Why is it so unusual? 3. Question: We discussed the different types of intermolecular forces in this lesson, which can affect the boiling point of a substance. Which of these has the highest boiling point? 4. Question: If you have 2.00 x 103 J of energy, what mass (g) of solid butane (C4H10O) can be melted? 5. Question: Question: We discussed different types of solid in this lesson. Which type of solid is dry ice (solid CO2)? 6. Question: We discussed different types of solid in this lesson. Which type of solid is chromium? 7. Question: Assume all of the following are liquids. Which has the highest vapor pressure? 8. Question: Why are water's chemical and physical properties so unique? 9. Question: We learned about phase changes, such as when a liquid turns into a gas (boiling). The temperature at which this occurs is known as the boiling point, which would be highest in which of these compounds? 10. Question: We discussed the different types of intermolecular forces in this lesson, one of which was the hydrogen bond. Which of the molecules below would have this type of intermolecular force? 11. Question: The phase diagram for CO2 has a triple point at –56.6 °C and 5.19 atm, and a critical point at 31.0 °C and 73 atm. The solid and gas phases are in equilibrium at –78.7 °C and 1.00 atm. Which of the following statements regarding CO2 is/are correct? 12. Question: The phase diagram for CO2 has a triple point at –56.6 °C and 5.19 atm, and a critical point at 31.0 °C and 73 atm. The solid and gas phases are in equilibrium at –78.7 °C and 1.00 atm. Which of the following statements regarding CO2 is/are correct? 13. Question: An element forms a body-centered cubic crystalline substance. The edge length of the unit cell is 287 pm and the density of the crystal is 7.92 g/cm3. Calculate the atomic weight of the substance. 14. Question: X-rays from a copper X-ray tube, at l = 1.54062 Å, are diffracted at an angle of 11.30o from a sample of metallic platinum. Assuming that n = 1, what is the distance between the planes that gives rise to this reflection? 15. Question: Rhodium (atomic mass 102.9 g/mol) crystallizes in a face-centered cubic unit cell. In addition, rhodium has an atomic radius of 135 pm. What is the density (g/cm3) of rhodium? 16. Question: Calculate the density of metallic copper, which has a face-centered cubic unit cell with an edge length of 361.5 pm. 17. Question: If you wanted to synthesize a compound that had a fairly low melting point and a low density, you would want to synthesize: 18. Question: Cesium has a radius of 272 pm and crystallizes in a body-centered cubic structure. What is the edge length of the unit cell? 19. Question: When a liquid is heated at its boiling point, the: 20. Question: A crystalline solid of unknown origin forms an aqueous solution that conducts an electrical current. The solid has a high melting point and shatters when struck with a hammer. The solid is likely to be:   21. Question: In liquid methanol, CH3OH, which intermolecular forces are present? 22. Question: Silver crystallizes in a face-centered cubic structure. What is the edge length of the unit cell if the atomic radius of silver is 144 pm? 23. Question: Lithium chloride crystallizes in a face-centered cubic unit cell with chloride ions occupying the lattice points and lithium ions occupying octahedral holes. How many chloride ions surround each lithium ion in LiCl? 24. Question: Determine the packing efficiency of a simple cubic unit cell that contains one atom with a metallic radius of 175 pm. 25. Question: Which one of the following is an example of a covalent network solid?