How do you estimate sulphate ion by nephelo turbidimetric analysis?

Answer 1

Convert sulphate into insoluble form. Most commonly used method for this is reacting the sample with barium chloride in presence of hydrochloric acid. Prepare formazine standards, calibrate nepheloturbidimeter and measure the NTU of the sample. Calculate the concentration of sulphate by extrapolation of the formazine standard curve.

Answer 2

In nepheloturbidimetric analysis, a turbidity meter measures the amount of light scattered by suspended particles in a sample. The increase in turbidity is proportional to the concentration of sulphate ions in the sample. By comparing the turbidity of the sample with a standard curve obtained from known concentrations of sulphate ions, the concentration of sulphate ions in the sample can be estimated.