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Analytical Method: Cobalt in water

Reagents:

Cat.No. 173016  Spectroquant® VIS Spectrophotometer Prove 100 or
Cat.No. 173017  Spectroquant® VIS Spectrophotometer Prove 300 or
Cat.No. 173018  Spectroquant® VIS Spectrophotometer Prove 600
Cat.No. 114946  Spectroquant® Rectangular cells 10 mm
Cat.No. 100456  Nitric acid 65 % for analysis
Cat.No. 106268  Sodium acetate anhydrous for analysis
Cat.No. 116754  Water for analysis
Nitroso-R salt (CAS 525-05-3)

 
Method:
10-mm rectangular cell
 
Working instructions:
Reagent 1: Mix 11 ml of nitric acid 65 % with 90 ml of water for analysis.
Reagent 2: Dissolve 5 g of sodium acetate anhydrous in 50 ml of water for analysis.
Reagent 3: Dissolve 0.25 g of Nitroso-R salt in 100 ml of water for analysis. The reagent can be used for approx. 4 weeks when stored closed and in a dark place.
 
Sample pretreatment:
In a 25-ml volumetric flask mix 10 ml of sample, 0.25 ml of reagent 1, 2 ml of reagent 2, and 1 ml of reagent 3. Make up to the mark with water for analysis, close flask, and remix.
 
Analysis:
Call up the saved method (# 305) in the Prove photometer and perform the measurement in a 10-mm rectangular cell at 495 nm against a blank prepared with water and the reagents in the same volumes as used for the sample.
 
Calculation:   Cobalt concentration in mg/l = Analysis result in mg/l

Materials

     
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