Hydrogen sulfide (H2S) is a common and troublesome pollutant in industrial

Chapter 20, Problem 14.98

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Hydrogen sulfide \(\left(\mathrm{H}_2 \mathrm{~S}\right)\) is a common and troublesome pollutant in industrial wastewaters. One way to remove \(\mathrm{H}_2 \mathrm{~S}\) is to treat the water with chlorine, in which case the following reaction occurs:

                                               \(\mathrm{H}_2 \mathrm{~S}(a q)+\mathrm{Cl}_2(a q) \longrightarrow \mathrm{S}(s)+2 \mathrm{H}^{+}(a q)+2 \mathrm{Cl}^{-}(a q)\)

The rate of this reaction is first order in each reactant. The rate constant for the disappearance of \(\mathrm{H}_2 \mathrm{~S}\) at \(28^{\circ} \mathrm{C}\) is \(3.5 \times 10^{-2} \mathrm{M}^{-1} \mathrm{~s}^{-1}\). If at a given time the concentration of \(\mathrm{H}_2 \mathrm{~S}\) is \(2.0 \times 10^{-4} \mathrm{M}\) and that of \(\mathrm{Cl}_2\) is \(0.025 \mathrm{M}\), what is the rate of formation of \(\mathrm{Cl}^{-}\)?