Homework Help: Chemistry

Posted by Xi on Friday, November 28, 2008 at 8:55pm.

I really don't get this. The calculations shown don't make sense.

Demonstrate that work is not a state function by calculating the work involved in expanding a gas from an initial state of 1.00: and 10.0atm of pressure to (a) 10,0 L and 1.0 atm pressure. (b) 5.00L and 2.00 atm and then to 10,0L and 1.00 atm pressure.

Solution
(a) w=-PV = -(1.00atm(10.0L-5.0L)
= -9.0L atm

(b) w=-PV = -(2.00atm)(5.0L-1.00L)-(0.0L- 5.0L)
=-13.0L atm

I don't see how the calculations correlate with what was given in the question.

Can someone please explain to me? Thanks!

Chemistry - GK, Saturday, November 29, 2008 at 1:41am
Referring to Part (b)
••Assume [PV] is a state function:
PV = (5 L)(2 atm) = 10 L.atm
PV = (10L)(1 atm) = 10 L.atm
∆(PV) = [PV]2 - [PV]1 = 10L.atm - 10L.atm = 0 work (not true)

••Actual work = -P∆V which could not be equal to 0 since P is not 0, and ∆V = is not 0. P varies from 2 atm to 1 atm., and ∆V = 5L.

For more in depth information on this check:
http://www.chem.arizona.edu/~salzmanr/480a/480ants/pvwork/pvwork.html

Answer this Question

Related Questions

Physics-totally bewildered!! - I have a physics question. This is for extra ...
college algebra - analyze the graph of the following function. r(x)= x^2+x-6...
Physical Chemistry - Derive an expression for number of electrons N(E) with ...
Physics (12th Grade) - In changing the state of a system from state A to state B...
physics, please help - its the second part of the question that I don't ...
Chemistry - What is the pressure (in atmospheres) of the gas inside the ...
math - The application of one function followed by the application of a second ...
Precalculus - The application of one function followed by the application of a ...
art 101 - According to the author, a. the interpretation of a work of art is ...
calculus - Give a reasonable sketch, on the axes provided, of the graph of the ...

For Further Reading

First Name:
School Subject:
Answer: