单选题The purpose of the ashing step in graphite-furnace atomic-absorption spec-troscopy is to（）AVaporize metal atoms to be analyzedBCause the metal species to form carbides which are more volatileCConvert the graphite furnace to ash to avoid carbide formationDBurn off organic species that would interfere with the elemental analysis
单选题
The purpose of the ashing step in graphite-furnace atomic-absorption spec-troscopy is to（）
A
Vaporize metal atoms to be analyzed
B
Cause the metal species to form carbides which are more volatile
C
Convert the graphite furnace to ash to avoid carbide formation
D
Burn off organic species that would interfere with the elemental analysis
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