Science Buddies: "Ask an Expert"

So for my project, I'm trying to find the surface tensions of varying liquids but I'm having a little bit of trouble trying to find a hypothesis. Would it make sense if i said liquids with a greater mass will have greater surface tension? And would the procedure in this link -- https://www.sciencebuddies.org/science- ... #procedure -- work for any liquids, not just water? Thanks.

Hello, and welcome to Science Buddies! You have chosen an interesting project.

Forming your hypothesis will be based on background research to gain as much knowledge as possible in order to make an educated guess about what your results will be. You will formulate your hypothesis based on what question you wish to answer with your experiment. You are measuring the surface tension of several liquids, but why are you measuring the surface tension? I can think of a couple of reasons:

1. Do you wish to compare surface tensions between the different liquids to determine which liquid has the lowest or highest surface tension?
2. Do you wish to determine how close the results of your experiment compare to published surface tension of the different liquids?
3. Is there another reason?

Once you determine your objective, then you can formulate your hypothesis. In the case of #1 listed above, your hypothesis could be:

1. There is no difference in surface tension among the different liquids.
2. Liquid x has the lowest / highest surface tension

Don't forget that your hypothesis must be something you can test!

Think about this and determine your objective and your resulting hypothesis. If you are still having problems, feel free to write back. I hope this helps. Good luck!

To second dnick96's advice, as you attempt to formulate your research hypothesis and question, background research will be particularly helpful in trying to form an educated guess about your project.

You're definitely on the right track asking questions such as if the density of a liquid will affect (or perhaps better stated as related/correlated) to it's surface tension. If this question interests you, you might try taking a variety of liquids (say honey, water, etc..) with different densities and test their surface tensions. The apparatus you described should in principle work for any liquid; though I've never built it/tried it so I'm not sure how easy it will be to use or accurate it will be.

Surface tension is a tricky concept, so reading more on Wikipedia (http://en.wikipedia.org/wiki/Surface_tension) will definitely be helpful. Some of the material in the article i s quite advanced so don't be discouraged! Let us know if you have any further questions on your project or article. Good luck!