As @ 1000 µg/mL in 5% HNO3, 100ml Back Catalog number: VHG-PASN-100 Availability: In the manufacturer's stock Price on request - + Recommended 54103 Nitrate (NO3-) as N, 1000µg/mL in Water, 100ml Price on request 54112 Ammonia as (NH4+) Price on request VHG-CLOIL-1P-100 Chlorine, 10000µg/g (1.00wt%) in Mineral Oil,100ml Price on request