docx GChem 112LS18 Vapor Pressure of Water and heat of Vapor

docx GChem 112L-S18 Vapor Pressure of Water and heat of Vaporization Post-lab questions Would you expect the vapor pressure of methanol to be smaller or larger than that of water at a particular temperature below the boiling points? 1. 2. Why does the partial pressure of air change with temperature? 3, why is the reciprocal temperature 1/T calculated in units of K1 instead of? Using your experimental data and slope equation, determine the vapor pressure of water at 90 4.

Solution

Answer 1.

Water forms strong hydrogen bonds between Hydrogen of one water molecule and oxygen atom of other water molecule. Similarly, hyderogen bonding is also possible in methanol molecules. However, the attraction between methanol molecules is not as strong as that exist between water molecules. Therefore, water will have the lower higher boiling point than methanol. Therefore, methanol will have the highest vapor pressure.