Immiscible
Science brain teasers require understanding of the physical or biological world and the laws that govern it.
We all know that oil and water just don't mix.
One thousand years ago, we also knew that everything revolved around the earth, and some people as recently as one hundred years ago knew that the earth was flat!
However, I know that I can get oil and water to mix simply by adding something found in every home.
Hint"Now with more grease-fighting power!"
Hide
Answer
What I add is dishwashing liquid! The reason oil and water don't mix is because oil is nonpolar, while water is polar. The "like dissolves like rule" explains why table salt (NaCl) can be dissolved in water (both are polar), while oil cannot (it's nonpolar).
What's special about the dishwashing liquid is that it is a surfactant, short for SURFace ACTing AgeNT. This gives it the ability to break the surface tension of water. Also, the molecules in the dish soap have one side that is polar and attracted to water and another that is nonpolar and soluble in oil, allowing both the polar water molecules and the nonpolar oil molecules to create a colloid called an emulsion.
There are different kinds of emulsions. Mayonnaise is an emulsion of vinegar and oil, which wouldn't mix if egg yolks weren't added.
Hide
Comments
Radioguy   
May 24, 2008
| Heh heh, I knew the answer, and I'm first to comment! Great teaser, and good explanation. |
safire2191
May 24, 2008
| nice teaser! I use an agent called tween at work. i think that may be the active ingredient. i could be wrong though |
tpg76
May 24, 2008
| Good teaser. But - a fairly contorted problem statement! (Flat earth??) I guess it comes with having your screen name!  |
dogzrok
May 24, 2008
| Very nice. I knew the answer when I saw it. Very.....long explanation....Great teaser. |
kunju 
May 25, 2008
| love it  |
rt1819
May 28, 2008
| What about a blender?? 
Fun teaser. |
tangled_brain
May 28, 2008
| hehe you could use a blender, but the oil would just clump back together once you turned it off.
try it! |
yangjun 
Jun 05, 2008
| this is very easy to answer but it is still fun as i LOVE science!!!!(especially chemistry)  |
drat
Jun 09, 2008
| yup soap is a simple emulsifier, but there are other things in the kitchen that do the same . love chemistry |
unklemyke
Aug 19, 2008
| And here I thought it was those scrubbing bubbles that did all the work. That'll teach me not to trust commercials.
Nice teaser. |
Paladin
Apr 09, 2009
| Fun and interesting. |
Back to Top
| |
|
