Question

V. (10pts) Calculate the root mean square speed, and the average speed of Ne(g) on a hot summers day when the temperature is 94.0°C Express your answers in both meters per second, and miles/hr. VI.(15pts) The following picture shows a gas entrapped in a sealed syringe with a movable plunger: (a)(7 pts) If the trapped gas is a hydrocarbon with empirical formula CH, and if the gas has a volume of 5.58 ml and a mass of 8.98mg at 45.0°C, and I atm pressure, what is the molar mass of the gas and what is its molecular formula? (b) (8pts) In a separate experiment, a gas phase reaction take place in the sealed syringe with the movable plunger. During the course of the reaction, the volume goes from an initial value of 50.0 ml. to 75.0 ml. at constant pressure and temperature of the reactions given in the following list, which took place indicate how you arrived at this result (a) 2A(R) +B(g) - > A,B (g) (b) A(g) + B(g) - > AB(g) (c) 2 AB(g) ---->A (8) + B(8) (d) 2 AB (8) ---->A.(B) + 2 B (8) (e) 2 A (8) + 4 Bg) ----> 4 AB(g) (Problem adapted from Moor, Stanistky, and Jurs Chemistry 2 ed chapter 10)

Answer 1

V) Temperature, T = 94°C +273 = 367 K Molar mass of Ne=20.2 g/mol Gas constant, R=8.314 K-m01-1 3RT RMS velocity of O, = VM Jx 1 kg.m/s? 1J 38.314 -_ 1J K.mol 20.2 g/mol 8.314 kg-m/ K.mol) (8314 kammoi) (367 K) 20.2 g/mol |$8:314 x10. Samo (367 K) 14x103 8.m/s2 K.mol 20.2 g/mol m 1 km 1 mi = 015 5 * 1000 m 1.60934 km =673 X- 3600 s 1hr = 1505 The Temperature,7 = 94°C +273 = 367 K Molar mass of Ne=20.2 g/mol Gas constant, R=8.314 K-mol-1 average velocity of Ne = 8RT VTM Jx1 kg.mp/s? Jx11 88.314 — (367 K) K.mol 3.14(20.2 g/mol) 8.314 kg.m/s?) (36 K.mol 3.14(20.2 g/mol) | 8 314x10 em 1907 ) 3.14 (20.2 g/mol) 1 km 1 mi 1000 m 1.60934 km 3600 s 1hr = 1388