Zimmermann-Reinhardt reagent

Zero percent T adjustment A calibration step that compensates for dark current in the response of a spectrophotometer. Zimmermann-Reinhardt reagent A solution of nianganese(II) in concentrated H2SO4 and HJPO4 that prevents the induced oxidation of chloride ion by permanganate during the titration of iron(II). 

Zimmermann-Reinhardt reagent (determination of iron). Dissolve 70 g of MnS04 4H2O in 500 mL of water, add 125 mL of cone. H2SO4 and 125 mL of 85% H3PO4, and dilute to 1 L. 

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