Is 10 and 15 because they both have a value of .909
The obvious answer is because propane is a gas at room temperature, while 2-propanol is a liquid at room temperature.
That happens because the intermolecular forces that exist between 2-propanol, or isopropyl alcohol, molecules are stronger than those that exist between propane molecules.
The great x value for what? Can you give us the equation?
