[G]

I graphed both the simple vs. fractional distillation....(Our unknown compound mixture is cyclohexane-toluene) What are the differences I should be looking for in graph comparisons? Why does the fractional distillation graph prove that fractional distillation is better for separation.

On the simple distillation graph, the curves go up and down and is all over the place...For the fractional distillation, the graph levels off at a good point...



 

[Arkcon]

Why does the fractional distillation graph prove that fractional distillation is better for separation.

Well, for your discussion ...

On the simple distillation graph, the curves go up and down and is all over the place...For the fractional distillation, the graph levels off at a good point...

... is a good starting point.  It's your experiment, those are your observations.  I can come up with a couple more, but that's Monday morning game officiating*, on my part.

In the US, we call that Monday morning quarterbacking, dunno what they say in countries where football is played with the feet.