Hydrochloric Acid Time - Hollow Cents - Science Experiment PMD

I filed a a tiny part of a zincoln with sandpaper than set it in rust remover (phosphoric acid) to try to get the same effect, it did not hollow up completely but certainly started to, I bet if I leaved it there longer it would hollow out.

 

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I must obey the Supreme Being, it's will is mine.

 

Oh man that's disappointing. I was not trying to create any harm for anyone. I'm sorry if this caused any problems. Not everyone had the same issue which is so strange. I use the full version of Norton and it was fine. It was a great webpage and a very interesting experiment.

 

Understood

 

I've found several versions of this experiment online by Googling "hollow penny hydrochloric acid". (Yes, I know, "cent"; if you want a successful search, use the more common term, not the "correct" one.)

I'd post links, but I don't know which link generated the virus warnings, and I don't want to make more work for the mods. @paddyman98 or @GDJMSP, if you'd be willing and able to PM me the original link, I can post some of the others.

 

Thanks. It's OK.. I think anyone interested in the experiment will be able to Google or Bing it themselves. Thanks for the info

 

Okay, there can't be that many people who are deeply interested in coins and chemistry and Javascript programming, so I guess I've nominated myself to go after this.

The troublesome page (which I won't link again here) would have been my FIRST choice to link, because it's clear, easy to read, well-designed, and completely ad-free. But it's got a chunk of "obfuscated code" at the bottom -- code that's been rearranged to be very hard to read -- and I'm guessing that that's what's set off Avast.

One strike against the page: there's no contact info anywhere on it. But I backed up to the parent company, and found an actual person (or at least a Google+ profile). I'll let him know that Avast is complaining about one of his pages, and maybe he'll get it sorted out.

 

Much too fragile for circulation.

Remember, the penny's copper is a thin coating.

So, after the zinc completely dissolves, the copper that remains is just a thin foil.

And very cool: Despite its fragility, the penny's details remain intact & clearly visible.

I did this demo every year for my high school chemistry students.

 

I knew that.. I was exaggerating just a bit..

Do you have any examples to share with us?

 

Instead, swimming-pool acid (aka Muriatic Acid) should work.

Use the stuff that's 31% hydrochloric acid (if you can find it): https://www.discountpoolmart.com/product_info.php/liquid-chlorine-and-acid/hasa-muriatic-hydrochloric-liquid-acid-24h-p-3142?osCsid=5e9b4246829c3eddffbffdbb0804ebc5

But for my chem students, I always soaked the scraped-edge penny overnight in 6M reagent-grade hydrochloric acid. Very clean.

And it doesn't take much acid. A full shot-glass is plenty.

 

Understood. But I'm new here, so figured I'd best play it straight.

I never saved any examples. And I retired from teaching many years ago, before I had a digital camera. So unfortunately no pictures.

 

Surprisingly, almost all my Chem students didn't know that modern pennies are copper-coated zinc. And that they weigh significantly less than pre-1982 pennies (3.1 grams vs 2.5 grams).

 

Well done. I had half an explanation written up friday but never posted because I figured no one else cared. I didn't go as deep as you did, but one of my points was that I've see antivirus software, the best money could buy, take out the web farm of the business who bought it because of a particular pattern of legitimate home grown code it didn't like. AV software is only as good as its latest signature files.

 

That probably doesn't stop me from posting nearly as often as it should.