How does one depict R= 1 × 10-6 , and subsequently a y-intercept of y = 6 × 10-6 on a y-x diagram? I'm new to the concept and very confused. From my understanding, this means that the reflux is essentially 0. It's also assumed that the distillate is purely vapour, so XD = 0 as there is no liquid fraction and XB = 0 because we're also assuming that all of the more volatile liquid is gas. The only other non-zero value is XF = 0.6. How would such a system look on a McCabe-Thiele graphical analysis? With my working I've ended up with 3 stages.