Oxidation of melted saltpeter

Chemicals needed

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small wooden sticks

Equipment needed

test tube
alcohol burner

Test procedure


The residues, being of such small quantity, can be discharged into the drainage. If a simple cleaning does not suffice, one can dissolve the saltpeter residue with diluted sulphuric acid, the adhering soot can be brushed off with alcohol.


Saltpeter acts under heat as a powerful oxidant, it splits off oxygen whereby the combustion or burning down occurs also without aeration. Thus is explained its historical use in propulsive or explosive charges, as well as in fireworks still today. Saltpeter is also used in analytical chemistry as an oxidation melt.


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In contrast to many anorganic salts saltpeter is easily melted.

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Wood smoulders away giving off smoke and soot in the melt.


Self-devised experimental procedure.