Question

The SO2 present in air is mainly responsible for the phenomenon of acid rain. The concentration of SO2 can be determined by titrating against a standard permanganate solution as follows:
5SO2 + 2MnO4 negative + 2H2O —> 5SO4 2 negative + 2Mn 2 positive + 4H positive

Calculate the number of grams of SO2 in a sample of air if 7.37 ml of 0.00800 M KMnO4 solution are required for the titration.

Answer 1

7.37mL/1000=0.00737L

n(MnO4-)=0.00800M*0.00737L=0.00005896 mol

n(SO2)=0.00005896mol*5/2=0.0001474mol

m(SO2)=0.0001474mol*64.05g/mol=0.00944g

Answer:m(SO2)=0.00944g