6.6、 Compound A and B are separated by a distillation tower. The ideal mixture follows Raoult’s
law and Dalton’s law. The saturated vapor pressure of compound A and B are 75 and 40
mmHg, respectively. The concentration of overhead product, feed, and bottom product are 0.9,
0.5 and 0.1, respectively. The feed is liquid at the boiling point. What is the value of the
minimum reflux ratio?
(A) 1.6 (B) 2.1 (C) 1.1 (D) 3.7
8.8、 The collection efficiency of a cyclone is 45% over the size range 0-5 mm, 80% over the size
96% for particles exceeding 10 mm. Calculate the total efficiency of
collection for the following dust: 50% 0-5 mm, 30% 5-10 mm, 20% above 10 mm.
(A) 86% (B) 71% (C) 53% (D) 65.7%
28.28、 Your heart beats at the rate of 70 times per minute, each beat pumping about 60 cm3
against a pressure of 120 mmHg. How much expansion work does the heart do in a day?
(Note: The heart work does much more work than this. The heart muscles are contracting, the
blood is accelerated, and there are frictional losses and other factors involved.)
J (B) 9.68×102
J (C) 9.68×103
J (D) 9.68×104
43.43、 What are the elements of the hierarchy of process design?
(A) Batch or continuous process (B) Input-output structure of process
(C) Recycle structure of process (D) General separation structure of process