Expert: John Dobiecki - 4/17/2005

Question
I added one teaspoon (up to 5) of salt to four cups of liquid and noted their boiling points.  The boiling point of baking soda, water and apple juice decreased.  While the boiling point of  grape juice and orange juice increased.  The boiling points of milk went down and then increased as I added more salt.  Do you think that I have correct results?  I am doing this experiment for a science fair project that is 30% of my grade.  I plan to graph the amounts of salt added compared to boiling temperatures for all of the liquids.  Thank you.

Answer
Ethan,

Your results suprise me.  The more stuff you add to liquid the lower I would expect the boiling point to be.  Maybe you went too fast when you were doing the experiments.  Worse case would be no detectable change in the boiling point, but never an increase.

Try it again and keep me posted.

jd