A dilute bleach sample containing Ca(OCI) was prepared by quantitatively diluting 25.00 mL stock bleach to 250mL using a volumetric flask. 25 mL aliquot of the diluted bleach solution was titrated using the previously standardized Na2S2O3 (Molarity = 0.0839).
50 mL of distilled water2.0 g of solid KI and 25 mL of 0.100 M H2SO4 and 5 drops 3% amnmonium molybdate catalyst were added to the analyte. The liberated I2 required 14.50 mL Na2S2O3 to reach the pale yellow solution after which starch was addedIt took additional 3.50 mL of the titrant for the blue color disappears. Calculate the M of Ca(OCI)2 (FW 142.98) in the STOCK solution.