Chem 1331 Midterm 2

1. What is the pressure, in ambience, of a armoured combat vehicle of spatter with a regulator that reads 1250mmHg? pupil receipt crystalize resolving A. 1. 64 B. 490 C. 1. 79 D. 0. 608 E. 1. 25 grievance 0/1 2. A 147. 9-L sample of teetotal air is cooled from 88. 0C to 22. 1C while the pressure is maintained at 2. 85 automatic teller. What is the final hatful in L? (Do non cause the units. ) pupil retort comprise termination dress non consequenceed 120. 9 tier 0/1 3. 1000 L of gas is prep ard in a tank at 700 mm Hg and 2000 oC. The gas is then transferred to a 40. L tank at 200o C. The pressure interior the new tank is Student retort ripe respond A. 14 mm Hg B. 70 mm Hg C. 280 mm Hg D. 1. 75 x 10 3 mm Hg E. 3. 64 x 103 mm Hg fit 0/1 4. The slow-wittedness of an unknown element in the aerosolised state is 1. 60 g at 300 K and 1 atm. Which of the chase could be the element? Student recepti on mend say A. He B. Ne C. Ar D. E. seduce 0/1 5. What is the pressure exerted by a intermixture of 0. 250 groynees of and 0. 400 molees of He at 27. 0C in a 3. 00 L container? Student receipt Correct help A. 16. 0 atm B. 5. 33 atm C. 3. 28 atm D. 2. 05 atm E. 1. 23 atm strike out 0/1 6. At 25C, an unknown gas, Q, diffuses at a deem 1. 65 times faster than that of propane, C3H8. Which of these gases is closely likely to be Q? Student solution Correct firmness of purpose A. O2 B. He C. Ne D. H2O E. CH4 Score 0/1 7. In the reaction below, what volume of PCl5 (g) go forth be produced by the reaction of 69. 7 L of chlorine gas with surfeit phosphorus (P4 if all gas volumes are measured at STP?P4 (g) Cl2 = PCl5 (unbalanced) Do not enter units with your adjudicate. Student chemical reaction Correct Answer Answer not answered 27. 9 Score 0/1 8. Consider threesome 5-L flasks, fitted with pr essure gauges and dwarfish valves, each contain a gas at 273 K. Flask A contains 4. 0 g of H2, flask B contains 4. 0 g of He, and flask C contains 8. 0 g of CH4. Compare the flasks contents in terms of the characteristics listed. total kinetic energy of the molecules. Student result Correct Answer A. Flask A Flask B Flask C B. Flask A Flask B Flask C C. Flask A = Flask B = Flask C D. Flask A Flask C Flask B E. Flask C Flask B Flask A Score 0/1 9. What is the change in internal energy (in J) of a system that absorbs 4. 07 kJ of wake up from its surroundings and has 0. 66 kcal of work make on it? 1 kcal = 4. 184 kJ Express your answer in scientific format with three significant figures 1. 25 x 103 = 1. 25E3 Do not type units. Student Response Correct Answer Answer not answered 6. 83E3 (6. 83 ? 103) Score 0/1 10. If addition of 25. 132 kJ of heat to a 0. 308 kg sample of an alcohol raises its temperature from 20. 0C to 46. 15C, what is the specific heat electrical condenser of the alcohol in J/g. K? Do not enter units with your answer. Student Response Correct Answer Answer not answered 3. 12 Score 0/1 11. Given the next equations acquire the enthalpy change (H) for the following reaction Student Response Correct Answer A. 844. 3 kJ/mol B. 483. 3 kJ/mol C. -241. 7 kJ/mol D. -483. 3 kJ/mol E. -844. 3 kJ/mol Score 0/1 12. High-purity benzoic acid (C6H5COOH ? Hcomb = 3227 kJ/mol) is a combustion standard for calibrating bomb calorimeters.A 1. 113 g sample burns in a calorimeter (heat capacity of calorimeter alone = 1365 J/C) that contains hardly 1. 200 kg of water. What temperature change volition be observed? Student Response Correct Answer Answer not answered 4. 60 Score 0/1 13. Using information from the text Appendix, augur ? H for the reaction. 2C2H6(g) + 7O2(g) = 4CO2(g) + 6H2O(g) Student Response Correct Answer A. 2855. 4 kJ B. 2855. 4 kJ C. 551 kJ D. 551 kJ E. none of these is within 5% of the correct answer Score 0/1 14. What weed of (g) must be burned to let loose 334 kJ of heat to the surroundings? Student Response Correct Answer A. 0. 426 g B. 6. 00 g C. 0. 375 g D. 2. 66 g E. 55. 6 g Score 0/1 15. An AM radio station broadcasts at about 1,031 on the radio dial. Units for AM frequencies are given in kilocycle (kHz). What is the wavelength of these radio transmissions in meters (m)? Type and the tour. Student Response Correct Answer Answer not answered 291 Score 0/1 16. A microwave photon has a frequency of 4,561 MHz.What is its energy in joules? land your answer in the form 1. 02E12 for 1. 02 x 1012 with three significant figures. Do not enter units with your answer. Student Response Correct Answer Answer not answered 3. 02E-24 (3. 02 ? 10-24) Score 0/1 17. What is the frequency (Hz) of a photon emitted by a hydrogen blood cell when its electron falls from n = 5 to 1? Enter your answer utilise exponential notation (1. 23 x 104 = 1. 23E4) with three significant figures and do not include units. Student Response Correct Answer Answer not answered 3. 16E15 (3. 16 ? 1015) Score 0/1 18. Which is not a possible ml care for for an orbital that has the following n = 2 Student Response Correct Answer A. +2 B. 1 C. +1 Score 0/1 19. Give the number of orbitals an atom can have with the following designation 3p Student Response Correct Answer A. 6 B. 2 C. 3 D. 4 E. an infinite number Score 0/1 20. Which subatomic mote was found to be present in cathode rays? Type its name only in the box. Student Response Correct Answer 1. not answered Equals electron (100%) Equals electrons (100%) Score 0/1