Finding temperature change, thermodynamics first law

[JoeyBob]

Homework Statement

see attached

Relevant Equations

PV=nRT

So I calculated the final and initial pressures using the given eqns, ended up with the final pressure of 96629 and initial pressure of 62639.

Then I used the PV=nRT eqn to calculate the final and initial temperatures. T=P*V/(n*1.5*R).

I got an initial temperature of 81.79 and a final temperature of 167.747, which is a change in temperature of 85.957 but the answer is 122.74.

 

[Chestermiller]

Homework Statement:: see attached
Relevant Equations:: PV=nRT

So I calculated the final and initial pressures using the given eqns, ended up with the final pressure of 96629 and initial pressure of 62639.

Then I used the PV=nRT eqn to calculate the final and initial temperatures. T=P*V/(n*1.5*R).

I got an initial temperature of 81.79 and a final temperature of 167.747, which is a change in temperature of 85.957 but the answer is 122.74.

So, is there a problem statement somewhere involved here?

 

[kuruman]

Also, attaching units to your numbers would be helpful.

 

[JoeyBob]

So, is there a problem statement somewhere involved here?

My bad. its attached to this reply

 

[kuruman]

Your pressures are way off. Please redo the calculation.

 

[Chestermiller]

I don't confirm either of the pressures you calculated. Also, what is that 1.5 factor doing in the denominator of your ideal gas temperature calculation?