Genchem 2 - Practice Test

1. Which of the following substances would have the greatest dispersion forces? A) H2 B) O2 C) Cl2 D) Br2 E) I2 2. Which of the following substances would not exhibit any hydrogen bonding interactions in a pure substance? A) H2 B) O2 C) Cl2 D) Br2 E) I2 3. Which of the following would exhibit hydrogen bonding in a pure substance? A) H2O B) HF C) N(CH3)3 D) CH3CH2OH E) CH3NH2 4. What intermolecular forces are present between two molecules of HI? A) Dispersion only B) Dipole-dipole only C) Hydrogen bonding only D) Dispersion and dipole-dipole E) Dispersion and hydrogen bonding 5. Which of the following exhibits dipole-dipole intermolecular forces in a pure substance? A) BF3 B) CO2 C) NH3 D) BR2 E) CF4 6. As a pure substance, which of the following could experience dipole-dipole interactions? I. CO¢ II. HCl III. CCl¤ A) I only B) II only C) III only D) II AND III only E) I, II, and III 7. As a pure substance, which of the following could experience dipole-dipole interactions? I. NO¢ II. NH£ III. N¢ A) I and II only B) I and III only C) II and III only D) I, II, and III E) None of the options experience dipole-dipole interactions 8. Consider the intermolecular forces present in a pure sample of each of the following compounds: CH£CH¢CH¢Cl and CH£CH¢CH¢OH. Identify the intermolecular forces that these compounds have in common. A) Dispersion forces only B) Dipole-dipole forces only C) Dispersion forces, dipole-dipole forces, and hydrogen bonding D) Dispersion forces and dipole-dipole forces 9. In a pure sample of O¢, what forces of attraction exist between the molecules? A) Dispersion forces only B) Dipole-dipole interactions only C) Both dispersion forces and dipole-dipole interactions D) Dispersion forces, dipole-dipole interactions and hydrogen bonds 10. Which of the following compounds can form intermolecular hydrogen bonds? A) H2Se B) HF C) HCl D) HBr E) All of these compounds can form hydrogen bonds 11. Which of the following intermolecular forces are present in a pure sample of CH£CH£? I. Dispersion forces II. Dipole-dipole interactions III. Hydrogen bonding A) I B) I and II only C) I and III only D) I, II, and III 12. Which is expected to have the lowest vapor pressure? A) CH4 B) SiH4 C) NH3 D) PH3 E) H2O 13. Which of the following has the lowest freezing point? A) H2O B) N2 C) SO2 D) H2 E) CO2 14. Which one of the following correctly ranks the compounds in order of lowest vapor pressure to highest vapor pressure based only in intermolecular forces? A) CH3CH2OH < CH3OCH3 < CH3CH2CH3 B) CH3OCH3 < CH3CH2CH3 < CH3CH2OH C) CH3CH2CH3 < CH3CH2OH < CH3OCH3 D) CH3CH2CH3 < CH3OCH3 < CH3CH2OH 15. Which one of the following correctly ranks the compounds in order of lowest enthalpy of vaporization to highest enthalpy of vaporization based only in intermolecular forces? A) CH3NH2 < CH3SH < CH3CH3 B) CH3NH2 < CH3CH3 < CH3SH C) CH3CH3 < CH3SH < CH3NH2 D) CH3SH < CH3NH2 < CH3CH3 16. Which term is a measure of the resistance to flow in a liquid? A) Adhesion B) Capillary action C) Cohesion D) Viscosity E) Surface tension 17. Which of the factors contributes to a low viscosity of a liquid? A) High boiling point B) Hydrogen bonding C) Compact molecular shape D) Low temperature E) High molar mass 18. Which of the following should exhibit the highest viscosity at 298 K? A) HOCH2CH2OH B) CH3OCH3 C) CH3OH D) CH3BR E) CH2CI2 19. Which quantity is not determined from a heating or cooling curve for a substance? A) Boiling point B) Heat of vaporization C) Triple point D) Melting point E) Heat of fusion 20. A phase change graph is shown below. Assume that pressure is constant. Choose the image that best represents which phase(s) are present at point A. A) I B) II C) III D) IV E) V 21. A phase change graph is shown below. Assume that pressure is constant. Choose the image that best represents which phase(s) are present at point B. A) I B) II C) III D) IV E) V 22. A phase change graph is shown below. Assume that pressure is constant. Choose the image that best represents which phase(s) are present at point C. A) I B) II C) III D) IV E) V 23. A phase change graph is shown below. Assume that pressure is constant. Choose the image that best represents which phase(s) are present at point D. A) I B) II C) III D) IV E) V 24. A phase change graph is shown below. Assume that pressure is constant. Choose the image that best represents which phase(s) are present at point E. A) I B) II C) III D) IV E) V 25. A phase change graph is shown below. Assume that pressure is constant. Identify what phase(s) are present at point A. A) Solid B) Solid and liquid C) Liquid D) Liquid and gas E) gas 1. What phase change is represented by the transition from B to C? a) Fusion b) Sublimation c) Vaporization d) Condensation e) solidification 2. Which of the following phases does a sample of water exist in at its triple point? a) Gas b) Liquid c) Solid d) All of these e) None of these 3. A phase diagram for CO¢ is shown below. Identify the critical point. a) Region II b) Region III c) Region IV d) Region V e) Region VI 4. A phase diagram for CO¢ is shown below. Identify the liquid region. A) Region I B) Region II C) Region III D) Region IV 1. Based only on intermolecular forces, which of the following would be the most soluble in CH£CH¢OH? a) CH3OCH3 b) CH3CH2CH2CH3 c) H2O d) CH3CH2OCH2CH3 2. Based only on intermolecular forces, which of the following would be the most soluble in CH£OH? a) CH3CH2OCH2CH3 b) CH3CH2OH c) CH3OCH3 d) CH3CH2CH3 3. CH£OH is soluble in H¢O. In C¥H¡¢, this solute would be: a) More soluble b) Less soluble c) Equally soluble 4. C¥H¡¢ is soluble in C§H¡¦. In H¢O, this solute would be: a) More soluble b) Less soluble c) Equally soluble 5. C¦H¡¤ is insoluble in H¢O. In C¥H¡¢, this solute would be: a) More soluble b) Less soluble c) Equally soluble 6. C¦H¡¤ is soluble in C¥H¡¢. In H¢O, this solute would be: a) More soluble b) Less soluble c) Equally soluble 7. Based only on intermolecular forces, which of the following pairs of molecules would be expected to form a nearly ideal solution? a) CH3CH2CH2CH2CH3 and CH3CH2CH2OCH3 b) CH3CH2CH2CH2CH3 and CH3CH2CH2CH3 c) CH3CH2CH2OCH3 and CH3CH2CH2CH2OH d) CH3CH2CH2CH2CH3 and CH3CH2CH2NH2 8. The phrase 'like dissolves like' refers to a) Two molecules having the same chemical formula b) Two molecules having the same intermolecular forces c) Two molecules having the same intermolecular forces d) Two molecules having the same temperature 9. One parts-per-billion means means 1 part of solute for every _____ parts of solution. a) 102 b) 103 c) 106 d) 109 10. One parts-per-million means means 1 part of solute for every _____ parts of solution. a) 102 b) 103 c) 106 d) 109 11. What is the molality of ions in a 0.341 m solution of Li£PO¤ assuming the compound dissociates completely?