Ammonium Standard: NH4+, 1000µg/ml in Water, 100ml Back Catalog number: VHG-INH41K-100 Availability: In the manufacturer's stock Price on request - + Recommended 59220 Method 6020Mix B Price on request 1720.13-K-IO 2-n-Propylnaphthalene, 1000µg/mL, Solvent-isooctane, Unit 1mL, # of units-1, Cas.no. 2027-19-2 Price on request 677876 4-tert-Octylphenol, 100 µg/ml, Acetone, 1ml Price on request