How to Find Final Temperature with Constant Pressure and Changing Volume

AI Thread Summary
To find the final temperature of the air in the cylinder, the problem involves 645 J of heat transferred to 0.185 mol of air at constant pressure. The initial conditions include a pressure of 3.00E6 Pa and a temperature of 780K, with the volume allowed to increase. The relevant equation for work done is W = p(V2 - V1), but the final volume (V2) is not specified, leading to confusion. The discussion suggests using the first law of thermodynamics, dE = Q - W, to potentially solve for V2. Clarification on the final volume is necessary to proceed with the temperature calculation.
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Homework Statement


645 J of heat is transferred to 0.185 mol of air inside a cylinder with volume 0.40 L. The air is at initial pressure is 3.00E6 Pa and temperature 780K.

Find the final temperature if the cylinder volume is allowed to increase while pressure remains constant.

Homework Equations


W=p(V2-V1)

The Attempt at a Solution



I have literally no idea how to do this problem. The examples in the book are (once again) unlike this problem. The question doesn't even make sense. It doesn't say what the final volume is.
 
Last edited:
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If the pressure remains constant, you know whatever work the cylinder does is given by W=p(V2-V1). Can you use dE=Q-W to solve for V2?
 

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