Wednesday, July 11, 2018

Crystal Growth for Dummies

Crystals in a cave
No light here, Megan...
One of the Antisocial Network staffers once spent a tortured semester as a fifth-grade teacher. We've seen her pull out those teaching tricks many a time, and one of our favorites is what she calls the reasonableness test. Take, for instance a barista making change: if you give him a twenty for your low-fat soy-milk mocha-latte and he gives back two tens in your change, he should realize something isn't reasonable. The same should have applied to eHowian Megan Shoop (and her content editor) when attempting to explain "The Best Growing Conditions for Crystals" at Sciencing.com.

Shoop apparently went straight to the science fair section of her extensive library (the one she collected while getting her BA in English Lit) and trotted out some conditions (at least she didn't use that word "considerations" for once). The conditions include,
  • Supersaturated Solutions
  • A Porous Crystal Foundation
  • A Warm and Light Atmosphere
We say, "Brava, Ms Shoop!" because those headings are actually on-target. It's when you get into the details of her "research" that Megan's ignorance of the topic crops up. Take, for instance, this claim:
"No matter what material you choose, your water must be supersaturated with it for crystals to grow."
That's not exactly true, Megan: a supersaturated solution just makes crystal growth start sooner and yields more crystal volume per volume of solution. It is not, however, absolutely necessary. By the way, supersaturation is difficult to achieve – saturation is much, much easier for the kiddos. About porosity, Shoop says,
"Porous materials work best as foundations for your crystals to grow easily. The air spaces allow the dissolved material to gain plenty of surface on the foundation..."
...which, IOHO, is a bizarre way to say that a rough surface has more total area than a smooth surface, although Megan's claim that
"...smooth, dense materials will not work because there is nothing for the crystals to grab onto..."
...is an overstatement: crystals will grow on glass! And finally, there's this completely bogus claim about warmth and light:
"Light evaporates water as heat does..."
This idiot must be kidding. If light is necessary for crystal growth, what causes the growth of crystals in caves? None of Shoop's references make that claim: like many an eHow.com contributor, she appears to have copied something that DMS rules wouldn't allow and then found a tangentially related website to claim as a reference. Content editors were usually just as lazy, so they never checked.

It appears that our Dumbass of the Day got confused as she was rewording a blog post somewhere (a homeschooling site?) and made matters worse. So what else is new?
    
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