Science Buddies: "Ask an Expert"

My 10th grade Science project will investigate why different liquids have different boiling points. What are common liquids should I select so I can buy/obtain? I am considering pure water, Vinager, witch Hazel, olive oil, alcohol. And how many liquids must be selected: 2 or 3? Thanks much, James

Hi,
I think you should experiment on three liquids: Water, Olive Oil, and Alcohol(Ethanol) because they all have very different boiling temperatures.
You might want to reconsider Witch Hazel if you're thinking of incorporating Witch Hazel in your project because I don't think Witch Hazel is a common liquid.

I think you should reconsider the safety of testing both olive oil and alcohol.

Boiling alcohol will give off flammable alcohol vapors. The boiling point of olive oil is very high and heating oil on your stove that hot is very dangerous. The smoke point of the olive oil is lower than the boiling point.

If you boil witch hazel or vinegar you should do it in a well ventilated area.

I would suggest you test how adding certain things to water can elevate or depress it's boiling point. For example, many people add salt to their water when they are boiling pasta to make it boil at a slightly lower temperature. You could investigate how different concentrations of salt change the boiling point.

Good luck!

Hi -
I'm trying to help my son come up with a title for his project. Project consists of comparing the boiling points of several liquids. Any suggestions?

Thanks.

Hi nmaciel,
What was the hypothesis for the experiment? I would recommend leading with that. (Something along the line of "Effect of x on Boiling Temperature) Probably not the most catchy title but could serve as a starting point.
Good Luck!
Willey