In The Big Bang Theory Season 3 Episode 1 "The Electric Can Opener Fluctuation"

Leonard gives Penny a snowflake that will never melt. He said some type of chemical gas name when he try to explain, but I don't understand what he said exactly so I can't do any research about that. You can watch it on this YouTube video as well.

I used Google for some searches like doesn't melt snowflake and insoluble snowflake but results gave me nothing.

So, is this possible to save a snowflake preserved in glass with a chemical element, gas or something?

  • $\begingroup$ This link looks promising: instructables.com/id/Catch-a-snow-flake-and-keep-it-forever $\endgroup$
    – Philipp
    Sep 27 '13 at 23:24
  • $\begingroup$ By the way Leonard used a 1 % solution of polyvinyl acetal resin. $\endgroup$
    – Philipp
    Sep 27 '13 at 23:24
  • $\begingroup$ @Philipp You have a reference or did you review your DVD collection? $\endgroup$ Sep 28 '13 at 1:14
  • 1
    $\begingroup$ @bobthechemist If you mean my statement concerning "polyvinyl acetal resin": I watched the scene from Big Bang Theory again and that's what Leonard says (at least it's what I understand). To back it up: here is another link which looks relatively trustworthy and where "polyvinyl acetal resin" is mentioned in the context of preserving snowflakes: its.caltech.edu/~atomic/snowcrystals/preserve/preserve.htm $\endgroup$
    – Philipp
    Sep 28 '13 at 1:24
  • $\begingroup$ @Philipp Yup, I was just curious. $\endgroup$ Sep 28 '13 at 13:38

With gas no absolutely. To preserve ice at room temperature using the pressure of a gas you should reach a pressure of one billion Pascals. Too dangerous for Penny safe...

In fact there are some imprecisions in the video Leonard cites two different methods to "preserve" snow flakes with an organic polymer. In fact these methods create a snow flakes replicas, they are called snow crystal fossils, because there is no more ice inside them. Both methods are describe here, have a look!

Formvar Replicas

Leonard: "it will last forever I preserve it in a 1% solution of polyvinyl acetal resin"

This is the Schaefer and Day technique [1] the solution Leonard is talking about is made from 1% of polyvinyl acetal resin in ethylene dichloride.

Superglue Replicas

Leonard: "in fact is a pretty simple process, you see, Cyanoacrylate are monomers which polymerize mmm... "

Cyanoacrylate are the main components of Super Glue this is easy method propose by the chemist Tryggvi Emilsson that you can do at home.

You have to choose one of these methods, you can't do both of them as Leonard (it seems) did... Take in account that Leonard is a physicist he doesn't know much about this stuff...;-)

[1] V. J. Schaefer and J. A. Day, Peterson Field Guides: Atmosphere (Houghton Mifflin, 1981).


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