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Q7 (NDA-I/2016) Science & Technology › Basic Science (Physics, Chemistry, Biology) › Applied everyday chemistry Answer Verified

The phosphorus used in the manufacture of safety matches is

Result
Your answer:  ·  Correct: A
Explanation

Red phosphorus is the specific allotrope used in the manufacture of modern safety matches. Historically, white phosphorus was used in 'strike-anywhere' matches, but it was phased out due to its extreme toxicity and high reactivity, as it can self-ignite in air at temperatures as low as 40°C. In contrast, red phosphorus is non-toxic and significantly more stable, with an ignition point above 200°C. In a safety match system, the red phosphorus is typically located on the striking surface of the matchbox rather than the match head itself. When the match is struck, friction converts a small amount of red phosphorus into white phosphorus, which then ignites and sets off the combustion of the match head chemicals, such as potassium chlorate.

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