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<p>[QUOTE="-jeffB, post: 25878020, member: 27832"]AAAAAUUUUGGGH</p><p><br /></p><p>1) DON'T DO THIS.</p><p>2) If you do do this, do it OUTSIDE. Dumping a bunch of methanol vapor into your indoors? Very stupid.</p><p>3) If you do do this, have a FIRE EXTINGUISHER close at hand. Methanol is <i>flammable</i>. Very flammable. Especially when vaporized.</p><p>4) If you do do this, maybe put the methanol into a <i>metal can</i> rather than a glass beaker. That way, thermal stress from the red-hot coin won't crack your beaker, as it cracked the one in the video. He's lucky it didn't crack enough to dump all the methanol across the table.</p><p>5) Methanol here is acting as a <i>reducing</i> agent, not an <i>oxidizer</i>. It reacts with the layer of copper and nickel oxides on the surface of the coin, combining with the oxygen and leaving the metal behind as a loose layer.</p><p><br /></p><p>When I did this as a kid, I heated a length of copper wire red-hot, then lowered it into the <i>vapor</i> above some methanol in a test tube. The wire had turned black from copper oxide, but it immediately turned bright copper-pink. There was a distinct smell of <b>formaldehyde</b>, which is what you get when you partially oxidize methanol. (It can also be oxidized further to formic acid, or all the way to carbon dioxide and water, but that's not what happened with the hot copper oxide -- it only went to formaldehyde.)</p><p><br /></p><p>Oh, yeah, and formaldehyde is also not great to breathe. Reread point 2 above.</p><p><br /></p><p>Sometimes I really hate YouTube "science" videos...[/QUOTE]</p><p><br /></p>
[QUOTE="-jeffB, post: 25878020, member: 27832"]AAAAAUUUUGGGH 1) DON'T DO THIS. 2) If you do do this, do it OUTSIDE. Dumping a bunch of methanol vapor into your indoors? Very stupid. 3) If you do do this, have a FIRE EXTINGUISHER close at hand. Methanol is [I]flammable[/I]. Very flammable. Especially when vaporized. 4) If you do do this, maybe put the methanol into a [I]metal can[/I] rather than a glass beaker. That way, thermal stress from the red-hot coin won't crack your beaker, as it cracked the one in the video. He's lucky it didn't crack enough to dump all the methanol across the table. 5) Methanol here is acting as a [I]reducing[/I] agent, not an [I]oxidizer[/I]. It reacts with the layer of copper and nickel oxides on the surface of the coin, combining with the oxygen and leaving the metal behind as a loose layer. When I did this as a kid, I heated a length of copper wire red-hot, then lowered it into the [I]vapor[/I] above some methanol in a test tube. The wire had turned black from copper oxide, but it immediately turned bright copper-pink. There was a distinct smell of [B]formaldehyde[/B], which is what you get when you partially oxidize methanol. (It can also be oxidized further to formic acid, or all the way to carbon dioxide and water, but that's not what happened with the hot copper oxide -- it only went to formaldehyde.) Oh, yeah, and formaldehyde is also not great to breathe. Reread point 2 above. Sometimes I really hate YouTube "science" videos...[/QUOTE]
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