This study source was downloaded by 100000795075979 from CourseHero com on 03 10 2023 02 34 11 GMT 06 00 https www coursehero com file 11468570 141 Exam 2 Fa13 Key Grossmont College Chemistry 141 Exam 2 Fall 2013Name Date Instructor Diana VanceExam 2Part 1 Multiple Choice 2 points each Directions Please circle the best answer for each of the following questions 1 Assuming ideal behavior which of these gas samples will have the greatest volume at STP a 1 g of H2b 1 g of Arc 1 g of O2d all of the abovee not enough information 2 Which of the following is true of the internal energy of a system and its surroundings during an energyexchange with a negative Esys a The internal energy of both the system and the surroundings increases b The internal energy of the system increases and the internal energy of the surroundings decreases c The internal energy of both the system and the surroundings decreases d The internal energy of the system decreases and the internal energy of the surroundings increases e none of the above 3 What is a photon a A packet of light b A packet of force c The smallest particle d The way of any interaction e Charge transporting particle 4 Using the graph below determine the gas that has the lowest density at STP This study source was downloaded by 100000795075979 from CourseHero com on 03 10 2023 02 34 11 GMT 06 00 https www coursehero com file 11468570 141 Exam 2 Fa13 Key f A g Bh C i Dj All of the gases have the same density at STP 5 Which statement is true about kinetic molecular theory k A single particle does not move in a straight line l The size of the particle is large compared to the volume m The collisions of particles with one another is completely elastic n The average kinetic energy of a particle is not proportional to the temperature o none of the above 6 A sun burn is caused by overexpose to radiation p ultravioletq gammar microwaves x rayt radio7 What value of the angular momentum quantum number l is represented by a d orbital u 0v 1w 2x 3y 4 This study source was downloaded by 100000795075979 from CourseHero com on 03 10 2023 02 34 11 GMT 06 00 https www coursehero com file 11468570 141 Exam 2 Fa13 Key Grossmont College Chemistry 141 Exam 2 Fall 2013Instructor Diana Vance8 Which statement is false z An exothermic reaction gives off heat to the surroundings aa Enthalpy is the sum of a system s internal energy and the product of pressure and volume ab Hrxn is the heat of reaction ac Endothermic has a positive H ad Erxn is a measure of heat 9 Two aqueous solutions are both at room temperature and are then mixed in a coffee cup calorimeter Thereaction causes the temperature of the resulting solution to fall below room temperature Which of the followingstatements is true ae The products have a lower potential energy than the reactants af This type of experiment will provide data to calculate Erxn ag The reaction is exothermic ah Energy is leaving the system during the reaction ai none of the above all statements are true 10 Which rule s about lab safety is true aj If a small piece of matter is lodged in the tip of a pipet buret or eye dropper it is acceptable to blow thepiece out with your mouth ak If a chemical smells good it must taste good and therefore it can be eaten al Eye protect is needed while you are reading or writing in the lab if other students are still performing theirexperiments am If a glass drops and shatters you should immediately pick up all large pieces with unprotected hands an You should deeply inhale all chemicals at the opening of the reagent bottle to smell it Page 3 of 8 This study source was downloaded by 100000795075979 from CourseHero com on 03 10 2023 02 34 11 GMT 06 00 https www coursehero com file 11468570 141 Exam 2 Fa13 Key Part 2 Short Answer Directions Answer each of the following questions Be sure to use complete sentences where appropriate Forfull credit be sure to show all of your work 1 In constructing a barometer what advantage is there in choosing a dense liquid 3 points A more dense liquid has a shorter column of liquid in a barometer and therefore we do not need to have a very tall barometer to measure atmospheric pressure 2 Determine the total volume of all gases at STP formed when 50 0 mL of TNT C3H5 NO3 3 density 1 60 g mL and molar mass 227 10 g mol react according to the following reaction 10 points 4 C3H5 NO3 3 l 6 N2 g O2 g 12 CO2 g 10 H2O g Or 3 What is the volume of 9 783 x 1023 atoms of kypton at 9 25 atm and 239 C 6 points 4 A gas bottle contains 0 250 mol of gas at 730 mm Hg pressure If the final pressure is 1 15 atm how many moles of gas were added to the bottle 6 points This study source was downloaded by 100000795075979 from CourseHero com on 03 10 2023 02 34 11 GMT 06 00 https www coursehero com file 11468570 141 Exam 2 Fa13 Key Grossmont College Chemistry 141 Exam 2 Fall 2013Instructor Diana Vance5 Why are the various forms of radiant energy called electromagnetic radiation 3 points All these forms of light have perpendicular oscillating electric and magnetic fields that traveltogether through space 6 How does the concept of an orbit in the Bohr model of the hydrogen atom differ from the concept of an orbital in quantum theory 4 points The Bohr model orbit showed the quantized nature of the electron in the atom as a particle moving around the nucleus in concentric orbits much like planets moving around the sun In quantum theory an orbital is a region of space where the probability of finding the electron is high The electron is not viewed as a particle but as a wave and it is not confined to a clearly defined orbit rather we refer to the probability of the electron being at various locations around the nucleus 7 How is Hess Law consistent with the law of conservation of energy 3 points When we apply Hess law all the heat is accounted for in the reaction energy is neither created nor destroyed when using Hess law 8 The mineral magnetite Fe3O4 is magnetic whereas iron II oxide is not 5 points a Write and balance the chemical equation for the formation of magnetite from iron II oxide and oxygen gas 6 FeO s O2 g 2 Fe3O4 s b Given that 318 kJ of heat are released for each mole of Fe3O4 formed what is the enthalpy change of the balanced reaction of formation of Fe3O4from iron II oxide and oxygen gas Page 5 of 8 This study source was downloaded by 100000795075979 from CourseHero com on 03 …