Quiz_ quizfirstlaw

2/14/24, 11:14 AM Quiz: quizfirstlaw https://sjeccd.instructure.com/courses/40778/quizzes/285805/take 1/9 quizfirstlaw Started: Feb 14 at 10:02am Quiz Instructions 2 attempts 90 minutes 2 pts Question 1 Five moles of an ideal gas expands isothermally at 100 ° C to five times its initial volume. Find the heat flow into the system. 2.5 × 10 J 4 1.1 × 10 J 4 6.7 × 10 J 3 2.9 × 10 J 3 7.0 × 10 J 2 1 pts Question 2 Beryl states that insulation with the smallest possible thermal conductivity is best to keep a house warm in winter, but worst for keeping a house cool in summer. Sapphire insists the reverse is true: low thermal conductivity is good in the summer, but bad in the winter. Which one, if either is correct? Beryl, because low thermal conductivity results in low heat transfer. Beryl, because low thermal conductivity results in high heat transfer. Sapphire, because low thermal conductivity results in low heat transfer. Sapphire, because low thermal conductivity results in high heat transfer.

2/14/24, 11:14 AM Quiz: quizfirstlaw https://sjeccd.instructure.com/courses/40778/quizzes/285805/take 2/9 Neither, because low heat transfer is desirable both in summer and in winter. 2 pts Question 3 If C for an ideal gas is 35.4 J/mol ⋅ K, which of the following is C for this gas? P V 12.5 J/mol ⋅ K 20.8 J/mol ⋅ K 29.1 J/mol ⋅ K 27.1 J/mol ⋅ K 43.4 J/mol ⋅ K 2 pts Question 4 One mole of hydrogen, one mole of nitrogen and one mole of oxygen are held in a 22.4 × 10 cm enclosed vessel at 20 ° C. The pressure in the vessel, in N/m , is 3 3 2 109. 304. 326. 1.09 × 10 . 5 3.26 × 10 . 5 2 pts Question 5 A slab of concrete and an insulating board are in thermal contact with each other. The temperatures of their outer surfaces are 68 ° F and 50 ° F. Determine the rate of heat transfer (in BTU/ft ⋅ h) if the R values 2

2/14/24, 11:14 AM Quiz: quizfirstlaw https://sjeccd.instructure.com/courses/40778/quizzes/285805/take 4/9 230 160 12 1 pts Question 8 The theorem of equipartition of energy states that the energy each degree of freedom contributes to each molecule in the system (an ideal gas) is 2 pts Question 9 A 5-kg piece of lead (specific heat 0.03 cal/g ⋅ ° C) having a temperature of 80 ° C is added to 500 g of water having a temperature of 20 ° C. What is the final equilibrium temperature (in ° C) of the system? 79 26 54 34 20

2/14/24, 11:14 AM Quiz: quizfirstlaw https://sjeccd.instructure.com/courses/40778/quizzes/285805/take 5/9 1 pts Question 10 Which of the following substances has the greatest specific heat? copper ice water steam Ice, water, and steam have equal specific heats since they are the same material, and this specific heat is greater than that of copper. 2 pts Question 11 Two tanks of gas, one of hydrogen, H , and one of helium, He, contain equal masses of gas. The gram- molecular mass of He is twice that of H . Both tanks of gas are at the same temperature, 293 K. Which statement(s) below is(are) correct when we ignore vibrational motion? 2 2 The total internal energy of the hydrogen is the same as that of the helium. The total internal energy of the hydrogen is 167 times that of the helium. The total internal energy of the helium is 1.67 times that of the hydrogen. The total internal energy of the hydrogen is 3.33 times that of the helium. The total internal energy of the helium is 3.33 times that of the hydrogen. 1 pts Question 12 Which of the following statements is correct? You only need to know the amount of thermal energy a body contains to calculate its temperature. The temperature of a body is directly proportional to the amount of work the body has performed.

2/14/24, 11:14 AM Quiz: quizfirstlaw https://sjeccd.instructure.com/courses/40778/quizzes/285805/take 7/9 1 pts Question 15 The internal energy of n moles of an ideal gas depends on one state variable T . two state variables T and V . two state variables T and P . three state variables T , P and V . four variables R , T , P and V . 2 pts Question 16 A gas expands from A to B as shown in the graph. Calculate the work (in joules) done by the gas. (1 atm = 1.01 × 10 N/m .) 5 2 12 24 1.21 × 10 6 2.42 × 10 6

2/14/24, 11:14 AM Quiz: quizfirstlaw https://sjeccd.instructure.com/courses/40778/quizzes/285805/take 8/9 3.64 × 10 6 1 pts Question 17 In an isothermal process the volume remains constant. the temperature remains constant. no heat is transferred between a system and its surroundings. the pressure remains constant. the internal energy is not constant. 2 pts Question 18 If the rms speed of helium atoms is v at temperature T , what is the rms speed of CO at the same temperature? rms,He 2 1 pts Question 19