4.10g of nitrogen gas at 20.0 C and an initial pressure of 2.70 atm undergo an isobaric expansion until the volume has tripled.
a. How much heat energy is transferred to the gas to cause this expansion?
b. The gas pressure is then decreased at constant volume until the original temperature is reached. What is the gas pressure after the decrease?
c. What amount of heat energy is transferred from the gas as its pressure decreases?