Julie H. Because the vapor pressure of a solution is lower than the vapor pressure of the pure solvent , it makes salt water (harder or easier...choose one) to boil than pure water
1 Expert Answer
Since the boiling point is defined as that temperature at which the vapor pressure of the solution/liquid is equal to the atmospheric pressure, adding a solute to make a solution will lower the vapor pressure and thus will raise the boiling point. So, it will make it "harder" to boil than pure water. The phrase "harder to boil" isn't exactly scientific, but that's the answer to the question as posed.