[apricimo]

Can someone explain the activity coefficient and the concept of "activity" intuitively. In other words what is activity 

Also fugacity.

Basically how do I think of it? My book derives and derives equations but I don't get an intuitive sense of these things.

[AWK]

http://en.wikipedia.org/wiki/Activity_coefficient

[apricimo]

Was hoping someone would contribute a bit more (i.e. activity of what or something to that affect). I think it's safe to assume people who post here have tried "googling" things before hand. Don't get me wrong links to sites are great, but I was looking for a human like (intuitive) explanation of these concepts.

[AWK]

 For human explanation take an appointment with your teacher.

Activity itself is method for using ideal chemistry laws for real solutions (and gases) and nothing more.

[Borek]

For human explanation take an appointment with your teacher.

So what's the point of chemicalforums then?

[Borek]

I think it's safe to assume people who post here have tried "googling" things before hand.

Our experience is quite opposite - most people ask questions without even trying to look in their textbooks, not to mention searching wikipedia or the net, to not explain the same things again and again we ask for some effort first.

Don't get me wrong links to sites are great, but I was looking for a human like (intuitive) explanation of these concepts.

Google "ionic atmosphere" - note that wiki article discusses it only in the context of conductivity; but concept applies to all reactions. Also note that so far sites are made by humans