A solution of pentane and ethanol CH3CH2OH that is 50.% pentaneby mass is boiling at 57.2°C. The vapor is collected and cooleduntil it condenses to form a new solution.
Calculate the percent by mass of pentane in the new solution.Here's some data you may need:
| normal boiling point | density | vapor pressure at 57.2°C |
| pentane | 36.°C | 0.63gmL | 1439.torr |
| ethanol | 78.°C | 0.79gmL | 326.torr |
Be sure your answer has the correct number of significantdigits.
Note for advanced students: you may assume the solutionand vapor above it are ideal.
