Re: Mini-volcano

[Brian Whatcott <inet@INTELLISYS.NET>]

At 02:41 PM 11/11/01 -0500, you wrote:
> Yes it is a neat demo.
> Ammonium dichromate decomposes to produce chromium(III) oxide, nitrogen gas
> and water vapor.  When this demo is presented in the open on a ceramic plate
> or on a heat resistant padded steel gauze, the green oxide fluffy flakes will
> tend to fly around and cause a mess.x\

/snip/

> Greg Darakjian


I will admit to a certain bias. I think ammonium dichromate is better
employed to
provide a  photo polymer of gelatin, which when applied to  a cloth and
exposed to a
u.v light shining through a high contrast photo or stencil in contact with
the cloth,
provides a delightful means of stippling paint onto a substrate when the
unlinked
gelatin is washed off, and the mask dried on a frame.

You may recognize this as a description of 'silk screen printing' .


Brian Whatcott
  Altus OK                      Eureka!