Answer to Question #305793 in General Chemistry for tecx

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

Millimoles of KMnO₄ = 100×0.008

=0.8

Millimoles = (ml × molarity)

5SO₂ + MnO₄^- + 2H₂O $\to$ 5SO₄^2-+ 2Mn²⁺+ 4H⁺

from equation , 1mole MnO^-₄ = 5mole SO₂

Therefore,

0.8millimoles MnO^-₄

$\implies$ 5× 0.8 millimoles SO₂

$\implies$ 4 millimoles SO₂