If 0.100 mol of an ideal monatomic gas has a pressure of 1.00 atm at 273 K and is cooled at constant pressure until its volume is one third its original volume.What is the amount of work done by the gas?

Question

Quizplus · Accepted Answer

We can use the formula for work done at constant pressure: w = -PΔV. 
The initial volume can be determined using the ideal gas law: PV = nRT 
V1 = (nRT1)/P1 = (0.100 mol)(0.0821 L·atm/mol·K)(273 K)/(1.00 atm) = 2.20 L 
The final volume is one third of the initial volume: V2 = (1/3)V1 = 0.733 L 
ΔV = V2 - V1 = -1.467 L (negative because the gas is being compressed) 
Substituting into the formula gives: w = -(1.00 atm)(-1.467 L) = 1.47 L·atm = -151 J 
The negative sign indicates that work is being done on the gas. Therefore, the answer is D.

If 0100 Mol of an Ideal Monatomic Gas Has a Pressure