A 6.27-g sample of an ant-control preparation was decomposed
by wet ashing with H2SO4 and HNO3. The arsenic
in the residue was reduced to the trivalent state with hydrazine. After the
excess reducing agent had been removed, the arsenic(III) was oxidized with
electrolytically generated I2 in a faintly alkaline medium:
The titration was complete after a constant current of 150.2
mA had been passed for 10 min and 34 s. Express the results of this analysis in
terms of the percentage As2O3 in the original sample.