10A10.30 - Carbide Cannon
Be sure to have fresh anhydrous Calcium Carbide on hand. Have a small beaker of water available which will be used to wet the carbide and liberate the acetylene. We have multiple shot cannon which is easier to operate as it stores enough carbide and water for multiple firings. Between shots you will need to blow out the smoke and old air in the cannon so that you have a fresh supply of oxygen for the next firing. Failure to do so will result in a faint pop instead of a loud bang.
The reaction is:
CaC2 + 2H2O -------------> Ca(OH)2 + C2H2(gas)
- DIY Archives, "Kiddie Cannon", Popular Science, May 2012, p. 76.
- Theodore Gray, "An Old Flame", Popular Science, June 2011, p. 90.
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