**A1.** Why is the still pot in Figure 9-2B much larger than the column?

**A2.** In the derivation of the Rayleigh equation:

**a.** In Eq. (9-4), why do we have −x_{D} dW instead of −x_{D} dD?

**b.** In Eq. (9-4), why is the left-hand side −x_{D} dW instead of −d(x_{D}W)?

**A3.** Explain how the graphical integration shown in Figures 9-3 and 9-5 could be done numerically on a computer.

**A4.** Suppose you have two feeds containing methanol and water that you want to batch distill. One feed is 60 mol% methanol, and the other is 32 mol% methanol. How do you do the batch distillation to obtain the largest amount of distillate of given mole fraction? N is constant.

**a.** Mix the two feeds together and batch distill.

**b.** Start the batch with the feed with higher methanol ...

Start Free Trial

No credit card required