Raoult's Law - Why does the volume increase and the mixture cool in a system with positive deviation?

Ethanol-cyclohexane system shows positive deviation from Raoult's Law. Why is this in molecular terms, and why does the volume increase and the mixture cool on mixing in a system displaying positive deviation?

Thank you in advance.

in +ve deviation the interaction of solute(A) and solvent(B) molecules is less than interaction of A-A or B-B molecules. so the volume increases and deltaH>0