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Vaporization and Pressure

Please explain how you get the answer for the following question:

How many kilojoules of heat are required to raise the temperature of 0.750 L of ethanol (d=0.789 g/mL) from 0.0 to 25 degrees Celsius and then to vaporize 10% of the sample? The specific heat of ethanol is 2.46 J g (to the -1 power) and degrees Celsius ( to the -1 power).

Solution Preview

In order to figure out the heat required for the whole process, you have to recognize that there are two different operations going on. First we heat the ethanol, then we vaporize (boil) the ethanol.

To heat the ethanol we use a simple formula:
q = mcDT (D =delta)
- m = mass of ethanol
- c = specific heat of ethanol
- DH = ...

Solution Summary

This solution is comprised of a useful guide to follow in order to complete this calculation based question. The steps to solving the problem are explained. Required equations and variables are provided. A student should be able to reach the final answer following the given instruction.