Chemistry - Entropy Changes in Physical Processes

by ncm2
Tags: chemistry, entropy, physical, processes
ncm2 is offline
Mar19-09, 10:40 AM
P: 16
1. The problem statement, all variables and given/known data
Indicate how entropy of the system changes for each of the physical processes shown below.
Entropy increases, entropy decreases, entropy does not change.

1. Purification
2. Mixing
3. Freezing
4. Evaporation
5. Separation

2. Relevant equations

Entropy increases when it goes from less to more disorder.
Entropy decreases when it goes from more to less disorder.

3. The attempt at a solution

Purification - many to one substance, so entropy decreases
Mixing - many to one substance, so entropy decreases
Freezing - more to less disorder, so entropy decreases
Evaporation - less to more disorder, so entropy increases
Separation - one to many substances, so entropy increases

These are wrong, but I can't think of why. Help is much appreciated.
Phys.Org News Partner Science news on
Lemurs match scent of a friend to sound of her voice
Repeated self-healing now possible in composite materials
'Heartbleed' fix may slow Web performance
Borek is offline
Mar19-09, 03:13 PM
Borek's Avatar
P: 22,654
Mixing - many to one substance... Do you mean that solution is ONE SUBSTANCE? What do you mean by one substance?

Register to reply

Related Discussions
Entropy - Physical Meaning Classical Physics 4
Entropy - physical system Introductory Physics Homework 1
Physical Chemistry Chemistry 1
physical chemistry Chemistry 1