homework 8.27

Moderators: Chem_Mod, Chem_Admin

Miya Eberlein 1J
Posts: 29
Joined: Fri Sep 25, 2015 3:00 am

homework 8.27

Postby Miya Eberlein 1J » Sun Jan 10, 2016 4:08 pm

In question 8.27 we're presented with two different pressures, one from the calibration of a piston and the other for an irreversible expansion. When solving for work done for both reversible and irreversible expansions, how do we know when to use which pressure?

Posts: 19640
Joined: Thu Aug 04, 2011 1:53 pm
Has upvoted: 891 times

Re: homework 8.27

Postby Chem_Mod » Mon Jan 11, 2016 1:50 am

For the reversible expansion, use the formula w=-nRTln(V2/V1). The initial pressure P=1.79 atm is given just so you can find the moles n using PV=nRT

For the irreversible expansion, the external pressure is given as held at 1 atm, and w = -Pext*deltaV.

Return to “Heat Capacities, Calorimeters & Calorimetry Calculations”

Who is online

Users browsing this forum: No registered users and 1 guest