Which of the following statements is true?
A. A binary liquid mixture will exist in two phases if the density of one of the pure components is much greater than the density of the other component.
B. If a liquid mixture exists in two phases, heating the mixture to increase the temperature will always cause the liquid to form a single liquid phase.
C. All liquid mixtures will either possess a UCST, an LCST or both.
D. All of the above are true.
E. None of the above are true.
A. Incorrect. The miscibility (or lack of it) is not a function of the densities of the components, but of the size difference of the molecules and their intermolecular interactions.
B. Incorrect. The system may possess only an LCST, so increasing the temperature will not cause the miscibility gap to disappear.
C. Incorrect. If two substances are completely miscible, they will never have a miscibility gap (the LLE “dome” in Figure 13-1) and therefore no critical solution temperature.
D. Incorrect. At least one statement is false. Please review the concepts related to the statements.
E. Correct. All of the statements are false.
You might also like to view...
Technician A says that oil pressure is normally higher when the engine is cold. Technician B says that normal engine oil pump pressure ranges from 20 to 80 psi (200 to 400 kPa) or 20 psi for every 1000 engine RPM. Which technician is correct?
A) Technician A B) Technician B C) Both technicians D) Neither technician
The starting device usually used on single phase, fractional horsepower motors requiring low starting torque is the ____.
A. potential relay B. current relay C. centrifugal switch D. differential relay
Ripsaws should be held at an angle of _____
a. 40 degrees c. 60 degrees b. 80 degrees d. 180 degrees
A welding symbol consists of a circle whose center is at the middle of the reference line. Two lines go through the circle parallel to the reference line, one above the reference line and one below it. To the left is the notation 0.22 and to the right is the notation 3.44. What does this welding symbol signify?
A. This symbol means that a continuous spot weld is to be placed between or upon overlapping members. The width of the weld is to be 0.22 inches, and the length of the weld is to be 3.44 inches. B. This symbol means that a seam weld is to be placed between or upon overlapping members. The width of the weld is to be 3.44 inches, and the length of the weld is to be 0.22 inches. C. This symbol means that a seam weld is to be placed between or upon overlapping members. The width of the weld is to be 3.44 inches, and the penetration of the weld is to be 0.22 inches. D. This symbol means that a seam weld is to be placed between or upon overlapping members. The width of the weld is to be 0.22 inches, and the length of the weld is to be 3.44 inches. E. None of the above. This is an incorrect symbol.