Author Question: Which of the following compounds could be subjected to sublimation at atmospheric pres sure? (a) ... (Read 41 times)

kamilo84 · **on:** Aug 23, 2018

Which of the following compounds could be subjected to sublimation at atmospheric pres
sure?
(a) Compound A: vapor pressure at its melting point = 770 mm Hg
(b) Compound B: vapor pressure at its melting point = 400 mm Hg
(c) Compound C: vapor pressure at its melting point = 10 mm Hg

Question 2

Limonene (MW 136) is a pleasant-smelling liquid found in lemon and orange peels. The bp of
limonene is 175, but it co-distills with water at 97.5. If the vapor pressure of water at 97.5 is
690 mm Hg, what percentage of the steam-distillate is limonene?

livaneabi · **Reply #1 on:** Aug 23, 2018

Answer to Question 1

Compounds A and B will have significant vapor pressure at their melting point.

Answer to Question 2

wtwater/wtlimonene = (690 x 18)/(70 x 136) = 1.3
Thus, for each 1.3 g of water, 1 g of limonene distills. Therefore, 1/2.3 g = 43 of the steam-dis
tillate is limonene.