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Wednesday, July 20, 2016

Mixing Oil with Water for Dummies

Oil and Water in an Emulsion
Oil and Water in an Emulsion
Like just about everyone else on Earth, our staff here at the Antisocial Network are familiar with the phrase "like oil and water." The phrase denotes two people, concepts, etc. that (supposedly) simply don't mix. Of course, having taken an elementary chemistry course or two (required of them, English or Journalism degree or not), our researchers are familiar with the concept of an emulsion – a mixture of oil and water (or any two immiscible liquids, for that matter). While attempting to teach about emulsions without not actually using the word, eHow.com's Kelly Sundstrom (BA in Music...) got herself into trouble with the post "How to Mix Water With Oil."

Although Sundstrom claims to be a home-schooling maven on her LinkedIn page, she went straight to "housekeeping" with this one in a rather strange introductory paragraph that starts out like this:
"There are certain substances that are known to be helpful in removing dirt and stains, like water, and certain substances that are helpful in cutting grease, like orange oil. Because oil and water do not naturally mix together, it is important to use another binding agent to help distribute the oils throughout the water."
OK, if she insists on calling it a "binding agent," we suppose that's OK; though we'd be more inclined to call the third substance in the mix an emulsifier or a surfactant, depending on how it does its thing. It's the next sentence, however, that tipped our researcher off to Kelly's scientific illiteracy...
"You can bind oil and water together effectively into a solution by adding a form of alcohol, such as vodka, into the mixture."
No, Kelly, wrong "science-y word": that doesn't create a solution, it creates an emulsion. There's a significant difference between the two: in a solution, one substance is dissolved in the other, e.g., salt in water, and the dissolved substance can't be separated out by physical means. In an emulsion, droplets of one substance are dispersed through the other substance by the emulsifier, but the droplets could be separated out physically and, in fact, often separate because of density differences. That's why the label on an emulsion such as salad dressing says to "shake before using" -- shaking disperses the droplets evenly
   

Now that the icky chemistry is our of the way, we thought we'd address Sundstrom's choice of emulsifer: vodka. Yep, she read somewhere that alcohol will do the trick, so she wants you to use a couple of shots of Ciroc or Ketel One (heaven forfend using the pomegranate-flavored stuff). Dumbass! Many alcohols act as an emulsifier, not just vodka. Of course, why one would use two ounces of vodka when there are surfactants all over the kitchen is a better question: instead of two ounces of vodka, why not use a few drops of liquid dish soap?

    As is often the case, the morons at Demand Studio slotted this "title" in the wrong section and therefore got a ridiculous answer. It belonged in what the mother site called "toys and hobbies" – yes, that's where these journalism grads put "science" – where it could be put to good use by first-time chemistry students and those showing kids the wonders of science. Instead, we got a Dumbass of the Day talking about cleaning. Ptui!
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