Apure substance has a boiling point of 80°c at 300 torr and 120°c at 600 torr. which of the following statements is true for this substance?
(1) its normal boiling point is below 80°c.
(2) its normal boiling point is above 120°c.
(3) it is stable as a liquid at 80°c and 200 torr.
(4) it is stable as a liquid at 200°c and 600 torr.
(5) none of the above statements are true.

Alice added sodium chloride to water and stirred the water for several minutes. alice is most likely trying to demonstrate that ionic compounds a. are hard. b. can dissolve. c. are clear. d. can melt.

Acylinder with a movable piston contains 11.7 moles of a monatomic ideal gas at a pressure of 1.32×10^5 pa. the gas is initially at a temperature of 300 k. an electric heater adds 43200 j of energy into the gas while the piston moves in such a way that the pressure remains constant. cp=20.79 j k^−1 mol^−1 for a monatomic ideal gas, and that the number of gas molecules is equal to avogadro's number (6.022×10^23) times the number of moles of the gas. (a) what is the temperature of the gas after the energy is added? (b) what is the change in volume of the gas? (c) how much work is done by the gas during this process?

Oxygen undergoes an isentropic expansion from 120 degree c and 280 kpa absolute to 140 kpa absolute. determine the final temperature of the oxygen and the amount of work per kg of o_2 produced in the process if it is adiabatic.