include sign w J q J include sign w J 6 8 6 2 CHEM230W16PREPE1 p 28 67 30 pts

# Include sign w j q j include sign w j 6 8 6 2

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include sign) w = J q = J ( include sign) w = J 6 8 6 2
CHEM_230_W16_PREP_E1 p 28 67) ( 30 pts ) Two identical, rigid containers (A and B) are connected by a valve. The valve is currently closed. Container A on the left contains 1 mole of CO gas at 250K and container B on the right contains 1 mole of N 2 gas at 300K. Assume that the gases act ideally unless otherwise stated. ( In each box below circle the one best answer. ) A 1 mol CO (MW = 28) B 1 mol N 2 (MW = 28) a) Which container contains more atoms? Container A Container B Neither b) Which container has the greatest gas density? Container A Container B Neither c) Which container has the molecules with the higher v rms ? Container A Container B Neither i) The nitrogen gas in container B was cooled to 250K before the valve was opened. After the valve was opened the total pressure in Container A is ( Circle one ) higher lower the same as the pressure in Container A before the valve was opened. d) Which gas will require more energy to raise its temperature by 10 K? CO N 2 Neither f) In reality, which gas acts most ideally at a high pressure of 1000 atm? CO N 2 they act similarly e) Which gas has the highest compression factor "Z" at a moderate pressure of 200 atm when compared at the same temperature? Briefly explain your answer addresing one or both van der Waals factors: g) What is the sign of the entropy change of the system when the valve is opened? S > 0 S = 0 S < 0 h) What is the sign of q for the N 2 gas when the valve is opened? q > 0 q = 0 q < 0 250K 300K CO N 2 not enough information 3 3 3 3 3 3 3 3 6
CHEM_230_W16_PREP_E1 p 29 71) For the following questions (a-i), consider the two Scenarios X and Y. 0.5 mol of helium is sealed in a container with a fixed volume of 6L at an initial pressure of 2 atm. The container of helium is initially at 20 o C and is heated to 250 o C. Scenario X Scenario Y 0.5 mol of helium is sealed in a flexible container with an initial volume of 6 L and a pressure of 2atm. The container of helium is initially at 20 o C and is heated to 250 o C. a) What is the sign of work for Scenario X? (Circle one) + - 0 cannot be determined b) What is the sign of work for Scenario Y? (Circle one) + - 0 cannot be determined c) Fill in the box with < , > , = , or X (for cannot be determined) q for Scenario X q for Scenario Y d) Fill in the box with < , > , = , or X (for cannot be determined) U for Scenario X U for Scenario Y e) Fill in the box with < , > , = , or X (for cannot be determined) S for Scenario X S for Scenario Y f) Fill in the box with < , > , = , or X (for cannot be determined) The density in container X when it reaches 250 o C The density in container Y when it reaches 250 o C h) Fill in the box with < , > , = , or X (for cannot be determined) The v rms in container X when it reaches 250 o C The v rms in container Y when it reaches 250 o C g) Fill in the box with < , > , = , or X (for cannot be determined) The collision frequency in container X when it reaches 250 o C The collision frequency in container Y when it reaches 250 o C i) Consider Container Y at 250 o C as the initial state. The contents of Container X at 250 o C are added to Container Y. As as result of the addition of all of the molecules from container X, which of