#### Transcript Chapter 10

Chapter 10 Practice Test Questions - Problems Multiple Choice – Question 1 1. An ideal gas confined in a box initially has pressure p. If the absolute temperature of the gas is tripled and the volume of the box is doubled the pressure is (A) p/8 (B) p/4 (C) 3p/2 (D) 2p/3 (E) 2p C) 3p/2 Multiple Choice – Question 2 2. An ideal gas in a closed container initially has volume V, pressure P. and Kelvin temperature T. If the temperature is changed to 2T, which of the following pairs of pressure and volume values is possible? (A) 2P and V (B) P and V (C) P and V/2 (D) P/2 and V (E) 2P and 2V (A) 2P and V Multiple Choice – Question 3 3. A mass m of helium gas is in a container of constant volume V. It is initially at pressure p and absolute (Kelvin) temperature T. Additional helium is added, bringing the total mass of helium gas to 5m. After this addition, the temperature is found to be 3T. What is the gas pressure? (A) 3 p (B) 3/5 p (C) 5 p (D) 5/3 p (E) 15 p (E) 15p Multiple Choice – Question 4 4. What temperature change on the Fahrenheit scale is equivalent to a 10 degree change on the Kelvin scale? (A) 283 K (B) 273 K (C) 18 K (D) 10 K (E) 0 (C) 18 F Multiple Choice – Question 5 5. According to the kinetic theory of gases, when the absolute temperature of an ideal gas triples, the average kinetic energy of the molecules of the gas (A) triples (B) one third (C) stays the same (D) is one sixth (E) is six times (A) triples Multiple Choice – Question 6 6. A new monatomic ideal gas is discovered and named “Gasium”. A pure 2-mole sample is sitting in a container at equilibrium in a 40.0ºC environment. According to the kinetic theory of gases, what is the average kinetic energy per molecule for this gas? (A) 4.14 × 10–22 J (B) 3652 J (C) 6.48 × 10–21 J (D) 2.02 × 10–21J (E) The molar mass of the gas is needed to answer this question. (C) 6.48 × 10–21 J Multiple Choice – Question 7 7. A monatomic ideal gas at pressure P = 105 Pa is in a container of volume V = 10 m3 while at temperature T = 30ºC. How many molecules of gas are in the container? (A) 447 (B) 2888 (C) 6.02 × 1023 (D) 2.39 × 1026 (E) 1.74 × 1027 (D) 2.39 × 1026 Multiple Choice – Question 8 8. One mole of an ideal gas has a temperature of 50°C. If this gas fills the 5.0m3 volume of a closed container, what is the pressure of the gas? (A) 0.821 Pa (B) 537 Pa (C) 83.1 Pa (D) 310 Pa (E) 1.84 × 1024 Pa (B) 537 Pa Multiple Choice – Question 9 9. Suppose the ends of a 20 m long steel beam are rigidly clamped at 0 oC to prevent expansion. The rail has a cross-sectional area of 50 cm 2. What force does the beam exert when it is heated to 80 oC? (steel = 1.1 x 10 –5/ oC, Ysteel = 2.0 x 10 11N / m 2). a. 8.8 x 10 5N b. 8.8 x 10 4N c. 1.76 x 10 6N d. 6.5 x 10 2N A) 8.8 x 10 5N Multiple Choice – Question 10 10. A steel wire, 125m in length at 10 oC, has a coefficient of linear expansion of 11 x 10 –6/C o. Give its change in length as the temperature increases to 75 oC. a. 0.65 cm b. 8.9 cm c. 0.89 cm d. 12 cm b. 8.9 cm Free Response Question 1. What is the vrms of oxygen molecules at 20 oC? Mass of O2 = 5.3 x 10 –26 kg; K b = 1.38 x 10 –23 J/K totalmass 5.3x1026 # moles 1.66 x1024 molarmass .032 # atoms (N A )(n) (6.02x1023 )(1.66 x1024 ) 1atom 5.3x1026 kg / atom mass 5.3x1026 kg 1atom vrms 3kbT 3(1.38x1023 )(293) m 478.4 s m 5.3x1026 Free Response Question 2. A 5.00 m3 container holds 12 moles of an ideal gas at a pressure of 2.30 x 104 Pa. What is the gas temperature? What is the vrms of the gas if it has a molecular weight of 28.0 x 10 -3 kg/mole? What is the KEavg for each molecule of gas? PV (2.30 x104 )(5.00) T 1153.2 K nR (12)(8.31) vrms 3RT 3(8.31)(1153.2) m 1013.3 s M 28 x103 3 3 KE K BT (1.38 x1023 )(1153.2) 2.39 x10 20 J 2 2