Cobalt standard reagent for dissolved cobalt analyses
Rinse a 100 mL volumetric flask  (that has been cleaned with 10% hydrocholoric acid cabinet) with pH 2 Milli-Q 3 times and Milli-Q 3 times.
Fill the flask part way with Milli-Q and add 29.5 μl of the cobalt AA standard (1 mg L-1) to the Milli-Q.
The final concentration will be 5 nmol L-1.
Carefully fill up to 100 mL Milli-Q using a squirt bottle and invert to mix.
Save a small aliquot in a 5 mL clean bottle for a potential run later on the ICP-MS.
