CHEM 121 FINAL EXAM Questions and Answers- PORTAGE LEARNING

CHEM 121 FINAL EXAM Questions and Answers- PORTAGE LEARNING A 5.00 liter gas sample is collected at a temperature and pressure of 27.0°C and 1.20 atm. It is desired to transfer the gas to a 3.00 liter container at a pressure of 1.00 atm. What must be the temperature of the gas in the 3.00 liter container? Select one: a. 216 K b. 417 K c. 13.5?C d. 150 K - ANSWER-d. 150 K .A colligative property Select one: a. will only occur for aqueous solutions. b. depends only on the number of species added to a solution. c. results from increasing vapor pressure as a solute is added to a solvent. d. All of the above. - ANSWER-b. depends only on the number of species added to a solution. .A gas sample is collected in a latex balloon (it can easily stretch or shrink). What happens to the density of the gas sample as the sample is heated? Select one: a. decreases b. increases c. does not change d. could increase or decrease, depending on how much it was heated - ANSWER-a. decreases .A mixture of sand and water would be an example of a colloidal suspension. Select one: a. True b. False - ANSWER-b. False .A pressure is recorded as 622 torr. What is this pressure in atm? Select one: a. 1.22 b. 0.818 c. 5.17 d. 0.0393 - ANSWER-b. 0.818 .A process that gains or accepts energy as it takes place is a(n) Select one: a. exergonic process b. spontaneous process c. endergonic process d. all of these - ANSWER-c. endergonic process .A reaction in which an acid and a base react completely, leaving only a salt and water is referred to as a Select one: a. hydrolysis reaction b. neutralization reaction c. oxidation reaction d. none of the above. - ANSWER-b. neutralization reaction .A salt sample is placed into some water and nearly all of it dissolves without stirring or heating. The resulting solution is Select one: a. saturated b. supersaturated c. unsaturated d. can't tell from the data given - ANSWER-a. saturated .A sample of gas collected at 21.0°C and a pressure of 660 torr has a volume of 1.83 liters. What volume in liters will the gas occupy at 38.0°C under a pressure of 500 torr? Select one: a. 2.56 b. 4.37 c. 2.28 d. 1.33 - ANSWER-a. 2.56 .A solution for which [H+] = 1.0 × 10-3 will have a pH of Select one: a. 5.00 b. 3.00 c. -5.00 d. -9.00 - ANSWER-b. 3.00 .A solution is made by combining 4.00 g of sugar and 100 mL of water (density = 1.00 g/mL). What is the concentration in % w/w? Select one: a. 26.0 b. 4.00 c. 0.0400 d. 3.85 - ANSWER-d. 3.85 .According to the law of conservation of matter, which of the following may NEVER occur as a result of a chemical reaction Select one: a. creation of new chemical species. b. reaction of starting materials c. rearranged to form new substances d. reduction in total mass - ANSWER-d. reduction in total mass .At 20°C, a sample of solid spontaneously sublimes to a gas. This change in state is accompanied by which of the following changes in the solid sample? Select one: a. entropy and energy decrease b. entropy and energy increase c. entropy decreases and energy increases d. energy decreases and entropy increases - ANSWER-b. entropy and energy increase .Attractive forces between solute and solvent molecules are an important factor in solution formation. Select one: a. True b. False - ANSWER-a. True .Catalysts may lower the activation energy. Select one: a. True b. False - ANSWER-a. True .Convert a temperature of 45°C into Kelvins. Select one: a. -45 K b. -228 K c. 228 K d. 318 K - ANSWER-d. 318 K .Decreasing the temperature will decrease the number of effective collisions. Select one: a. True b. False - ANSWER-a. True .Definite shape is a characteristic of which state of matter? Select one: a. solid b. liquid c. gaseous