Let's remember what a non ideal fluid is. A non ideal fluid is a fluid in which the volume of molecules is not neglected and intermolecular forces connecting the molecules exist. And these forces will play a role in decreasing the vapor repression of the fluid. And we'll see that in a second. Now, before we talk about that, let's talk about the heat of solution. Now, we have already spoken about heat of solution in another video, so let's briefly discuss it.