(a) Mixture of two liquids showing high boiling azeotropic behaviour.
It is formed by a non ideal solution showing negative deviation from Raoult's law. The vapour pressure vs mole fraction plot of such solutions shows a minimum. Total vapour pressure for any mole fraction is less than that expected from Raoult's law. The new interactions are stronger than the interactions in the pure components. For such solutions, the enthalpy of mixing and the volume change on mixing are negative.
(b) Mixture of two liquids showing low boiling azeotropic behaviour.
It is formed by a non ideal solution showing positive deviation from Raoult's law. The vapour pressure vs mole fraction plot of such solutions shows a maximum. Total vapour pressure for any mole fraction is more than that expected from Raoult's law. The new interactions are weaker than the interactions in the pure components. For such solutions, the enthalpy of mixing and the volume change on mixing are positive.
What molecular features determine whether a mixture of two liquids will show high- and low-boiling azeotropic...
Water boils at 100 °C. Ethanol boils at 78.4 °C. A mixture of these two liquids forms an azeotrope at a composition of XH,0 =0.08 and XEtOH = 0.92. The boiling point of the azeotropic mixture is 78.2 °C. Suppose you prepare a azeotropic mixture of ethanol and water, with 21,0 = 0.08. If you distill this solution (i.e.: boil the solution, collect some of the early vapor that is produced, and condense it), then the resulting solution (called the...
3. A mixture of two miscible liquids with widely different boiling points is distilled. The temperature of the vapor is observed to plateau and then drop before rising again. Explain this temperature drop. (3 points) 4. If you doubled the length of the fractional distillation column, what would be the advantages and disadvantages? (3 points) 5. Why is better separation of two liquids achieved by slower heating of a mixture? (3 points)
a) For an ideal mixture of two liquids A and B, show that the pressure p! at which the mole fractions of A in the gas and liquid phases are most different from one another is given by the geometric mean of the partial pressures of pure A and B.
1) Why is the column packing material used in the fractional distillation column? 2) What should be the characteristic features of an ideal column packing material? 3) Two fractional distillations are run with identical mixed samples of two liquids using different columns. In apparatus A, the column is 15 em long, and in apparatus B, the column is 25 cm long. Will one apparatus provide any better separation of the mixture then the other? If so which one and why?...
12 Study the following phase diagram for an ideal mixture of two liquids A and B and answer the questions that follow: 102 94 81 Pressure/kPa 66 50 43 40 I DET 0 0.2 0.4 0.6 0.81 XA What is the vapour pressure for the pure compound B. 12.1 Page 2 of 4 [2 marks] 12.2 Determine the value for Xin a mixture of composition x = 0.30. [2 marks] 123 At what pressure will a mixture of composition X095...
what is high and what is low. What are two nutrients that should be high and two that should be low.
9. Large intermolecular forces in a substance A) low vapor pressure B) high boiling point C) high heats of fusion and vaporization O) high critical temperatures and pressures E) all of the above are manifested by 10. Of the following A) CBr4 is the most volatile. B) CCl4 C) CH4 D) CF4 E) C6H14 Refer to the phase diagram below to complete questions 11-13 1.5 P (atm) 1.0 0.5 0 100-1-20 30 40 50 6070 T C'C) 11. What is...
2. Aliquid mixture contains two substances whose boiling points are only 10°C apart. Which method of distillation should be utilized to obtain a clean separation of the two substances. Explain. 3. Which of the following pairs of liquids could be separated by simple distillation? Why? a. Ethyl acetate (b.p. 77°C) & Phenol (b.p. 181.7°C) b. Cyclohexane (b.p. 80.7°C) & Toluene (b.p. 111C) C. Hexane (b.p. 69.10C) & Ethylbenzene (b.p. 136°C) 4. What effect would (a) an increase or (b) a...
ya heterogeneous mixture. D) a homogeneous mixture. 27) What is the percent by mass of hydrogen in NalICo A) 27.4 % B) 1.20 % C) 24.7 % D) 44.2 % 28) Which one of the following formulas is the empirical formula of glucose (Cali2Oo)? A) CHO B) CH20 C) C2H4O2 D) C4Hs04 29) A compound with the empirical formula C2HCI was found in a subsequent experiment to have the molar mass of approximately 181.45 g/mol. What is the molecular formula...
during the experiment to determine molecular weight through boiling point elevation we recieved a molecular weight much lower than what it should have been , what would be the reasoning for this to occur