Module 2 Redox titration Bromo and Bromatometric titration N

Module 2. Redox titration. Bromo- and Bromatometric titration. Nitritometry Variant 1 Mass of N 1. Solution of potassium bromate was prepared by dissolving the sample 0.0556 g of potassium bromate in 200.00 ml volumetric flask. Calculate the molar concentration Mass fracs of equivalent of the solution and titer of potassium bromate by arsenic (II1). 2. Calculate the mass of sodium nitrite you need to prepare 250.00 ml of 0.05 N solution of sodium nitrite. Calculate the titer by sulfanilic acid of the prepared solution.

Solution

1. Potassium bromate is an oxidising agent which when titrated with As (III) helps in the redox estimation of arsenic by oxidising the sample. From the molar mass of potassium bromate of 167.00g/mol the molar concentration of a solution prepared by dissolving 0.0556g in 200mL of solution is given by the formula Molarity = (Mass/Molar mass)*(1000/Volume) = (0.0556/167)*(1000/200) = 1.6646x10^-3M.

From the balanced redox reaction between potassium bromate and arsenic (iii) involves oxidation of arsenic (iii) to arsenic (v) with the consumption of reagents in a 1:3 ratio.