During the iodide-catalyzed decomposition of thiosulfate, S O

CHEMISTRY · Single correct · AP · Chemistry · Properties of Substances and Mixtures · Properties of Substances and Mixtures

Problem

During the iodide-catalyzed decomposition of thiosulfate, S

_2

_3^{2-}

, a blue transient species S

_2

_3^{•-}

is monitored spectrophotometrically at 615 nm. The path length of the cuvette is 1.00 cm, and the molar absorptivity at 615 nm is

1.8\times10^{3}\,\text{M}^{-1}\text{cm}^{-1}

. If the absorbance at 0.50 s is 0.090, what is the concentration of S

_2

_3^{•-}

at that time? (a)

1.8\times10^{-4}\,\text{M}

(b)

5.0\times10^{-5}\,\text{M}

(c)

2.2\times10^{-5}\,\text{M}

(d)

5.0\times10^{-6}\,\text{M}