certified reference material, in acetonitrile (varied conc.), ampule of 1 mL Components: Acetaldehyde-2,4-dinitrophenylhydrazone 1000 μg/mL; Acetone-2,4-dinitrophenylhydrazone 500 μg/mL; Acrolein-2,4-dinitrophenylhydrazone 500 μg/mL; Benzaldehyde-2,4-dinitrophenylhydrazone 500...