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75 solutions

Internal Energy

Q. A block of CO2 weighing 15.0 g evaporates in a balloon at STP. The balloon fills to 5.00 L. The enthalpy of sublimation for CO2 is 25.1 kJ/mol. What total energy in kJ is available from the sublimation of dry ice in kJ?

Solved • Mar 28, 2020

Internal Energy

Q. A chemical reaction is performed in a flask that is sealed with a piston. The initial volume of the system is 0.550 l and the final volume is 0.375 l. The pressure remains constant at 1.00 atm. Calculate the amount of work performed in joules

Solved • Mar 27, 2020

Internal Energy

Q. An ideal gas (the system) is contained in a flexible balloon at a pressure of 1 atm and is initially at a temperature of 20 °C. The surrounding air is at the same pressure, but its temperature is 25 °C. When the system has equilibrated with its surroundings, both systems and surroundings are at 25 °C and 1 atm. In changing from the initial to the final state, which one of the following relationships regarding the system is correct? A. ΔE < 0 B. ΔE = 0 C. ΔH = 0 D. w > 0 E. q > 0

Solved • Mar 23, 2020

Internal Energy

Q. Which of the following is both a greenhouse gas and a fuel? A. nitrogen B. methane C. carbon dioxide D. freon E. coal

Solved • Mar 23, 2020

Internal Energy

Q. The combustion of carbon with excess oxygen forming carbon dioxide is exothermic. C(s) + O2(g) => CO2(g) ΔHrxn = -393 kJ If 8,334 kJ of heat is needed from the combustion, how much carbon (g) must be consumed? Enter your answer in decimal format and do not include units.

Solved • Mar 23, 2020

Internal Energy

Q. A fuel-air mixture is placed in a cylinder fitted with a piston. The original volume is 0.290-L. When the mixture is ignited, gases are produced and 865 J of energy is released. To what volume will the gases expand against a constant pressure of 635 mmHg, if all the energy released is converted to work to push the piston? A. 10.5 L B. 1.65 L C. 9.93 L D. 10.2 L E. 7.42 L

Solved • Mar 23, 2020

Internal Energy

Q. Calculate the work associated with the expansion of a gas from 42.0 L to 79.0 L at a constant pressure of 13.0 atm. A. -1.03 x 10^3 L•atm B. 546 L•atm C. -481 L•atm D. 481 L•atm E. 1.03 x 10^3L•atm

Solved • Mar 23, 2020