A solution of carbon tetrachloride and carbon disulfide containing 50% by weight of each is to be continuously distilled at a rate of 5000 kg/h.
(a) Determine the concentration of the mixture in terms of mole fractions. (b) Determine the average molecular weight of the mixture.
(c) Calculate the feed rate in kmol/h.

(a) CS₂ = 0.331, CCl₄ = 0.669; (b) 102 g/mol; (c) 49.1 kmol/h

Explanation:

Assume 5000 kg of mixture.

(a) Mole fractions

(i) Mass of each compound

Mass of CCl₄ = 2500 kg

Mass of CS₂ = 2500 kg

(ii) Moles of each compound

(iii) Mole fractions

Total moles = 16.3 kmol + 32.8 kmol = 49.1 kmol

The major component is usually called the solvent — Component 1 —carbon disulfide.

(c) Average molar mass

The average molar mass is the weighted molar mass of each component.

(d) Feed rate

answer: c. the experiment shows that the red substance experienced a chemical change.

explanation: chemical change is the change in which chemical composition of the substance changes. physical change is the change in which there is no change in chemical composition.

chemical changes are accompanied by following changes:

a) precipitate formation

b) energy is released or absorbed

c) formation of bubbles

d) change in color

as it is given that the red color has disappeared and there is production of gas, it means the red substance has undergone a chemical change.

e

c. heat could easily travel through the molecules in the air and escape/enter the flask. removing the air slows down the heat transfer.