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OK, here we go indeed =) I hope this is not useless work.

Chemical Snakes

For hundreds, if not thousands of years, chemists conduct spectacular experiments in which the products of chemical reactions appear as snakes crawling out of the reaction zone. Some of these reactions are quite simple, so why don't we try them on our own ? Let's start with the simlest snake - the soda snake.

1. Soda snake

Make a little pile of sifted sand, make a small crater in it and pour alcohol generously into it (just take care to not wash out the pile of sand). Try to pour directly into the center of the crater.

http://www.mntc.ru/projects/snakes/8015.jpg

Prepare the reaction mass. What can be simpler - take on part of baking soda (sodium bicarbonate) per four parts of powdered sugar (aka confectioner's sugar, icing sugar etc.), and mix thoroughly with a stirrer in some small vessel.

(on the picture: baking soda, powdered sugar)

http://www.mntc.ru/projects/snakes/8026.jpg

Place then the reaction mass in the crate on top of the sand pile. Ideally, the mixture should be slighly less than the crater; otherwise you may get a mutant snake with horns and tentacles.

http://www.mntc.ru/projects/snakes/8017.jpg

Carefully iginite the alcohol. Don't foget about fire safety ! At first, black balls and other boring stuff will appear...

http://www.mntc.ru/projects/snakes/8022.jpg

...And then THE SNAKE crawls out ! (video, 2x speed: http://www.mntc.ru/projects/snakes/01.wmv)

http://www.mntc.ru/projects/snakes/8007.jpg

http://www.mntc.ru/projects/snakes/8005.jpg

http://www.mntc.ru/projects/snakes/8023.jpg

Impressive, isn't it ? Imagine how this trick, perforemed by alchemists or high priests, impressed the people of antiquity, who had aboslutely notion of chemistry, but believed in magic =)

The snake-creating reactions are:

http://www.mntc.ru/projects/snakes/r.jpg

The more alcohol you put - the longer the snake is. It consists of a hard foamy material, similar to burnt paper or a wasp nest. This is sodium carbonate with carbon particles in it. Carbon dioxide, produced in the reaction, makes it foamy. In the beginning the foam forming is pretty much random, but the process is more stable later on; this forms an articulate "head", followed by the "body", which strengthens the likeness to a snake. The snake formation ends when the alcohol is exhausted, leaving the snake with a white piece of unreacted mixture.

http://www.mntc.ru/projects/snakes/8011.jpg

WARNING ! NEVER add more alcohol after the burning is complete. The sand is burning-hot, so the very first drops of alcohol may ignite, igniting the whole stream and alcohol in the vessel you are holding. This may end quite sadly for you.