Chem 1331 Midterm 2

1. What is the gouge, in atm, of a tank of muck up with a regulator that reads 1250mmHg? disciple Response set per resile A. 1. 64 B. 490 C. 1. 79 D. 0. 608 E. 1. 25 come to 0/1 2. A 147. 9-L example of dry ambience is cooled from 88. 0C to 22. 1C while the pressure is maintained at 2. 85 atm. What is the final volume in L? (Do non type the units. ) savant Response countersink consequence cause non resolutioned 120. 9 hit 0/1 3. 1000 L of mishandle is prepared 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 inside the new tank is learner Response Correct conclude 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 crisscross 0/1 4. The density of an unknown element in the gaseous state is 1. 60 g at 300 K and 1 atm. Which of the following could be the element? educatee Response Correct Answer A. He B. Ne C. Ar D. E. tick 0/1 5. What is the pressure exerted by a mixture of 0. 250 moles of and 0. 400 moles of He at 27. 0C in a 3. 00 L container? Student Response Correct Answer A. 16. 0 atm B. 5. 33 atm C. 3. 28 atm D. 2. 05 atm E. 1. 23 atm Score 0/1 6. At 25C, an unknown gas, Q, diffuses at a RATE 1. 65 times faster than that of propane, C3H8. Which of these gases is most likely to be Q? Student Response Correct Answer A. O2 B. He C. Ne D. water system E. CH4 Score 0/1 7. In the reaction below, what volume of PCl5 (g) leave alone be produced by the reaction of 69. 7 L of chlorine gas with excess phosphorus (P4 if all gas volumes are measured at STP?P4 (g) Cl2 = PCl5 (unbalanced) Do not infix units with your answer. Student Response Correct Answer Answer not answered 27. 9 Score 0/1 8. Consider leash 5-L flaskfuls, fitted with pressure gauges and small 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 qualification of the molecules. Student Response Correct Answer A. flaskful 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 heat from its purlieu and has 0. 66 kcal of work done on it? 1 kcal = 4. 184 kJ Express your answer in scientific format with three epoch-making 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 hear of an alcohol raises its temperature from 20. 0C to 46. 15C, what is the specific heat force of the alcohol in J/g. K? Do not enter units with your ans wer. Student Response Correct Answer Answer not answered 3. 12 Score 0/1 11. Given the following equations Determine the total heat 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 merely 1. 200 kg of water. What temperature change will be observed? Student Response Correct Answer Answer not answered 4. 60 Score 0/1 13. Using information from the text Appendix, calculate ? 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. no(prenominal) of these is within 5% of the correct answer Score 0/1 14. What mass of (g) must be burned to release 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 receiving set station broadcasts at about 1,031 on the radio dial. Units for AM frequencies are given in kilohertz (kHz). What is the wavelength of these radio transmissions in meters (m)? Type only the function. 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? Enter 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 pinpoint when its electron falls from n = 5 to 1? Enter your answer using exponential notation (1. 23 x 104 = 1. 2 3E4) 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 value 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 constituent 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 particle 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