So You’re Taking a Standardized Test…

Oh boy, that’s a “fun” way to start. Standardized tests are scary, and nerve-wracking; you just want to do well, and God help you if you only have a mechanical pencil left in your backpack…!
Then comes the dreaded moment: you have made a mistake (or you think so, at least) and need to erase a bubble.
But what if the machine doesn’t pick up my erased answer? What if it smudges? What if I use up my whole eraser and rip a hole in the paper?!

Agh, so stressful. It’s times like these where you should be glad for erasers that work.

Even I’m transitioning from thick paper binder to sleek Apple Macbook following my return to school after winter break, but according to How It’s Made (I love this website) Americans still use more than 2 billion pencils every year.

First of all, if you didn’t find out in third grade, pencils are made from graphite, not lead. If it were lead, I’d probably have fallen terribly ill by now. Erasers work by lifting particles of graphite off of the paper fibers.
Modern erasers are almost always made from petroleum-based synthetic rubber compounds, typically polyvinyl chloride. (Actual rubber is an allergen for some people!)

The particles in the polymer that make up the eraser are a lot stickier than paper, so they pick up most of the graphite particles off the paper pretty well.
Seems basic, but actually pretty cool when you think about it on a molecular level. Little itty bitty polymer particles lifting itty bitty graphite particles off of itty bitty paper fibers!

Well, most of them. If you have a bad eraser like I did taking my PSATs, you’ll be stressing about the streaky gray marks on your answer sheet for days.
I should start being more organized like Tara over at Chemical Reaction….

 

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One thought on “So You’re Taking a Standardized Test…

  1. Hey Sarah! Thanks for the shout out! And I don’t think carrying around 72 zillion pencils for a test counts as being organized. More like being prepared! Anyway, if you ever need an extra pencil, or other school supplies, you know who to ask! Keep up the great work! I love reading your blog!
    For more chemistry, because you can never have too much chemistry, check out my blog at tflstar89.wordpress.com

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