Gases Multiple Choice Test
Click in the appropriate box for each question, then click "Done" at the bottom. 10 marks for each correct answer. Hints cost 5 marks each.
1. STP means: 25oC and 1 atm 298oC and 1 atm 298 K and 0 atm 273.15 K and 0 atm 0oC and 1 atm
2. The ideal gas law is valid: At low temperature and high pressure At low temperature and low pressure At high temperature and high pressure At high temperature and low pressure Under all conditions of temperature and pressure
3. The relative rate of effusion (or diffusion) of CH4 (MW = 16) to that of O2 (MW = 32) is: 1 : 2 2 : 1 1.41 : 1 1 : 1.41 4 : 1
4. The ideal gas law fails at high pressures because: The gas molecules are moving too fast The gas molecules are undergoing so many collisions The gas molecules are closer together, resulting in repulsive forces and hence a higher pressure than predicted The gas molecules are closer together, resulting in attractive forces and hence a lower pressure than predicted None of the above
5. The contribution of a gas to the Greenhouse Effect is due to: The radiative forcing of the gas The reactivity of the gas in the atmosphere The quantity of the gas emitted into the atmosphere All of the above None of the above
6. The Cl atom can effectively destroy ozone because: We emit large quantities of Cl-containing species into the atmosphere Cl acts catalytically to destroy ozone The reaction between Cl and ozone is very fast The Cl is not effectively removed via other reactions All of the above
7. The partial pressure of carbon dioxide in the atmosphere is approximately 350 x 10-6 atm. Which of the following is true? The mole fraction of CO2 in the atmosphere is 350 x 10-6 The concentration of CO2 in the atmosphere is 350 parts per million (ppm) The volume fraction of CO2 in the atmosphere is 350 x 10-6 None of the above All of the above
8. When a gas is collected over water: The partial pressure of the gas can not be calculated The partial pressure of the gas is equal to the total pressure minus the vapor pressure of water The partial pressure of the gas is equal to the vapor pressure of water plus the total pressure The partial pressure of the gas is equal to the total pressure None of the above
9. The molar volume of chlorine gas is slightly less than that of helium because: Chlorine is a smaller molecule than helium Helium atoms repel one another more that chlorine molecules do Chlorine molecules attract one another more than helium atoms do Chlorine is diatomic None of the above
10. The average speed of a gas molecule: Is larger for lighter molecules Is larger at higher temperatures Is greater than the most probable speed Is inversely proportional to the mean free path of the molecule All of the above