Author: Vera Koester.gif "How Does a Match Work? - ChemistryViews (1)")
Why does a match burn? Why does it ignite only on the friction surface of the matchbox?
- Friction on the ignition surface:
P4 + 5 O2 –→ P4O10
If the match is struck against the striking surface, the friction causes the match to heat up. A small amount of the red phosphorus on the friction surface is converted into white phosphorus. The heat ignites the phosphorus that has reached the match head of the match when rubbing.
- Redoxreaction (example):
3/4 S8 + 4 KClO3 –→ 6 SO2 + 4 KCl
This triggers the reaction between sulfur or antimony sulfide and oxygen. The oxygen is supplied by the oxidizing agent potassium chlorate.
The match head mass is foamed with air to optimize the burning behavior of the match head. Silicates are added to the match head, which on the one hand, dampen the reaction somewhat and thus prolong the burning time, and on the other hand, form a slag that prevents the ash from being separated from the match.
- Combustion of the wood (cellulose):
(C6H12O6)m + 6m O2 –→ 6m CO2 + 6m H2O
In addition to the match head, a match consists of the actual wood impregnated with ammonium dihydrogen phosphate and dipped in paraffin. In the third phase, the fire spreads to the paraffine and then to the wood. In the process, the wood chars and forms charcoal. It would continue to glow after the flame has gone out. The impregnation with ammonium dihydrogen phosphate prevents this afterglow so that after the flame is extinguished, the match is completely extinguished.
Reference
- Match Head Reaction, University of Washington Department of Chemistry (accessed August 31, 2020)
As an enthusiast with a deep understanding of the topic, I'd like to shed light on the fascinating science behind the combustion of a match. The process involves a series of chemical reactions and carefully designed components that contribute to the ignition and sustained burning of the match.
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Friction and Ignition Surface:
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The friction on the match's striking surface initiates the heating process.
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Red phosphorus on the friction surface converts to white phosphorus due to the heat generated.
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The ignited white phosphorus then spreads to the match head.
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Chemical Reaction: [ P_4 + 5O_2 \rightarrow P4O{10} ]
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Redox Reaction and Oxidizing Agent:
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A redox reaction occurs between sulfur or antimony sulfide and oxygen.
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The oxidizing agent, potassium chlorate, provides oxygen for the reaction.
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Example Redox Reaction: [ \frac{3}{4} S_8 + 4 KClO_3 \rightarrow 6 SO_2 + 4 KCl ]
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Match Head Composition:
- The match head is foamed with air to optimize burning behavior.
- Silicates are added to dampen the reaction and extend burning time, forming a slag preventing ash separation.
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Combustion of Wood (Cellulose):
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The match includes wood impregnated with ammonium dihydrogen phosphate and dipped in paraffin.
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The combustion process involves cellulose in the wood.
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The wood chars and forms charcoal, which could continue to glow after the flame is extinguished.
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Ammonium dihydrogen phosphate prevents afterglow, ensuring complete match extinguishment.
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Combustion Reaction: [ (C6H{12}O_6)_m + 6m O_2 \rightarrow 6m CO_2 + 6m H_2O ]
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References:
- The information provided is based on the "Match Head Reaction" from the University of Washington Department of Chemistry, accessed on August 31, 2020.
Understanding these intricate details highlights the careful balance of chemical components and reactions involved in the seemingly simple act of striking and igniting a match.
