Chemical Stability and Compatibility - Cold storage for Cr(VI) standards
I was emailing to get your opinion on the storage conditions for a 1000 ppm Cr(VI) standard prepared with K2CrO4. Currently, we store the standard at 0-4 deg. C. Is this not an appropriate storage scheme?
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admin
Total posts: 529
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We are not aware of any specific reason why cold storage (0-4 C) would be necessary for a 1000 ppm Cr(VI) standard (hexavalent chromium). While we do not have extensive stability data for a standard made from K2CrO4, it is likely that a 1000 ppm Cr(VI) standard stored at room temperature (18-25 C) would be chemically stable indefinitely. We do have a stock 1000 ug/mL Cr(VI) standard made from (NH4)2Cr2O7 that is stored at room temperature and which has a demonstrated chemical stability that exceeds 3 years.
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