[jessianne]

Hey! I am absolutely stumped on these 2 chemistry questions! If anyone could please guide me in the right direction that would be great!!

-You place 1600 mL of C₂H₅OH in an air tight container measuring 3.0 ft x 1.3 ft x 2.0 ft. The temperature is held at a constant 25.0 degrees Celsius. Will all the C₂H₅OH vaporize? Vapor pressure of C₂H₅OH at 25 degrees Celsius is 86.4 mm Hg and the density is 0.79 g/mL.

I answered no because temperature must be greater than boiling point in order for it all to vaporize but my work isn't working out! My container measurement is 13478 cubic centimeters while my answer using vapor pressure was .408 cubic centimeters. I am not exactly sure of the relation between to two.


ANY HELP WOULD BE GREATLY APPRECIATED!!

-An ice cube tray contains enough H₂O at 22.0 degrees Celsius to make 18 ice cubes (each has a mass of 30 g). 6 identical ice cube trays are placed in a freezer that uses CF₂Cl₂ as a refrigerant. What mass of CF₂Cl₂  must be vaporized to convert ALL the H₂O to ice at -5.0 ddegreesCelsius? H_VAP for CF₂Cl₂ is 158 J/g.

I know that H_VAP=19.1043 KJ/mol and also that the 6 trays=3240g but what is throwing me off is the fact that i have to find the mass of CF₂Cl₂!! I can't use the cClausiuscClapeyronformula and the ideal gas law PV=nRT!

[Borek]

If you put glass of water in any place for long enough it will dry out regardless of the temperature (assuming it is shielded from rain ). So there is no need for temperature above boiling point.