Naked Science Forum
Non Life Sciences => Chemistry => Topic started by: paul.fr on 01/08/2007 22:32:42
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why do they light on different surfaces?
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That is a good question but I would think the compounds used to make the different varieties must be altered for that purpose maybe slightly changed to effect the desired results. maybe one is treated with a coating to prevent lighting .. the regular ones seem softer when lighting..the red part seems less coated etc.
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Safety Matches - (Supposedly) can only be ignited by rubbing the match head on the stricking suface of the match box. One of the ingredients needed for the ignition is contained within the stricking surface on the box. Red phsphorus on the stricking suface is converted into white phosphorus in response to the friction of the match head. White phosphorus is needed for ignition.
Strike Anywhere Matches - I think these can be lit by stricking on any abrasive surface. Sandpaper, brick, the bottom of a shoe, or a rough belt buckle will do the trick. I even have a friend who can lite one off of his tooth. These contain white phosphorus in the match head. In most cases the normally red match-heads have a white tip.
I'm not sure which type would be considered "regular matches"
There are also "waterproof matches" which produce a much hotter flame, and burn much faster. They produce a ~5 second "torch." While camping on a rainy day these can be quite handy. I've been told they can be lit underwater but I'm not sure if that's possible.
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Many thanks, CC
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Sorry to extend this but I was told that there were civilisations which managed to light flames underwater. Was that naphtha? And does it take oxygen from the water, or am I on the wrong track?
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There's probably no way that a flame could get enough oxygen to be sustained from the dissoled oxygen in water. There would have to be an oxidant contained in the flame's source, such as those in underwater expolsives. (probably nitro compounds)
Naptha (hydrocarbon chians) would float on the surface, and doesn't have the oxygen required to burn underwater.
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Strike Anywhere Matches - I think these can be lit by stricking on any abrasive surface. Sandpaper, brick, the bottom of a shoe, or a rough belt buckle will do the trick. I even have a friend who can lite one off of his tooth. These contain white phosphorus in the match head. In most cases the normally red match-heads have a white tip.
Are you sure they contain white phosphorus? It's highly toxic, I think it should be forbidden to use it; furthermore, white phosphorus reacts by itself with air oxygen, so the match wouldn't be very stable.
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Your right! After some further research, they now use a compound called phosphorus sesquisulfide, which is contained in the match head, and produces a similar effect to white phosphorous. I guess that's the white colored compound that composes the red match head's white tip.
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Good research you guys!
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I wrote a potted history of matches and safety matches about 3 years ago. Here's the link:
http://www.thenakedscientists.com/forum/index.php?topic=350.msg12887#msg12887
Chris