Chemistry Question #884

Jason Bever, a 32 year old male from Valrico, Florida asks on August 19, 2002,

At a bar a fellow was doing a bar trick in which he asked anyone for a piece of foil from: cigarette pack/ gum wrapper or aluminum foil from kitchen. Any thing with foil. He then would dip it in beer or water whatever was available (as far as i could tell) then he folded it up very small and placed it in one's hand and the foil ball would heat up too hot to handle. The foil then looked "oxidized", flaky and white powdery. I'm assuming this is a chemical reaction he created by adding or having maybe salt or something else come in contact with the foil? Can you help me decide how he did this? the process of adding water and the folding was done in plain sight..what ever he added or did to cause the reaction was very descreet...any help will be greatly appreciated!

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The answer

Barry Shell answered on August 29, 2002

I used and looked in "Groups" and found the answer in rec.pyrotechnics from a fellow named Chris Spurrell:

There's an old "Bar bet" wherein the person takes the Aluminum foil from a cigarette pack, wets is with some Hg2Cl2 and pinches it between both thumbs and forefingers, and says "I bet you can't hold in your hand what I've got in mine." The sucker accepts the "gift" of reactive Al foil and gets a burn as the air oxidation causes it to heat up. The Bichloride of Mercury used to be available as an antiseptic.

The chloride ion will break down the oxide layer on the aluminum, allowing the aluminum to oxidize assuming there's some water present to ionize the mercurous chloride.

Rick Ramby answered on September 30, 2002

It is called hypno heat and it is a magic trick using mercury compound. You can order it online. Search hypno heat and go from there. Some places only sell it to professional entertainers because of mercury involvement, and most of those places recommend not using it at all because of skin absorbtion and mercury poisoning possibilities.

Steve Gillihan, 15, Utah high school student answered on November 14, 2005

You can use mercuric chloride (HgCl2) as well. It does the same trick. But both these compounds can be very dangerous if not handled carefully. I would not advise using anything that involves mercury. Both these mercury compounds easily combine with protein to form highly toxic organomercury compounds. If mercuric chloride absorbs through your skin it can cause problems with your nervous system and other things. Inhalation is another problem. From my own personal experience i can tell you not to try this trick. After watching our school instructor perform the tin foil trick, I took some mercuric chloride home and wanted to demonstrate to my friends. I accidentally got my fingers wet while rubbing the mercuric chloride onto the tin foil. To make a long story short, I ended up with some pretty serious chemical burns as well as heat burns. It caused some corrosion on my thumb, middle finger and pointer finger. Mercuric chloride is quite expensive, costing about $90 for 500 grams.

Pete Lane from UK answered on October 29, 2007

I saw this trick performed whilst serving in the RAF in Salalah (Oman in the 1970s). I have susequently read all the information on Hypno-heat. The person who preformed it was a mechanic who worked with batteries; it was unlikely he had Hypno-heat. I suspected it was sodium hydroxide (caustic soada) I tried it recently and it works and the heating effect decays fairly rapidly. Only a few grains are required and of course moisture. Took me 30 years to get the answer.

David Nash answered on December 21, 2009

A bottle of pharmaceutical grade mercury bichloride bought in 1981I did the Bi-chloride of Mercury trick hundreds of times, over a period of about 40 years. The chemical was sold in the form of a light blue colored pill. (See photo of bottle from 1981.) Rubbing the pill on the tip of a wet forefinger transferred (loaded) enough blue chemical to achieve the desired effect. It was easy to conceal the blue color on the tip of the loaded forefinger. If the magician uses the loaded forefinger to fold the foil, the foil will get hot in the subject's hand.

R. K. Moore answered on September 15, 2013

My Dad paid 100 for this trick in the 50's and drank for free many nights at local bars thru the 90's. Kept a tablet in his pocket 24/7 and would rub it with his fingers just before a "performance". His old bottle of BiChlor. of Merc. had a cork, and inside were blue four-sided diamond-shaped tablets with a skull and crossbones stamped into each one. he lived till 87 and didn't die from Bichlor. of Merc. poisoning.

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