When solid \(\mathrm{KClO}_{3}\) is heated strongly, it decomposes to form solid
potassium chloride, \(\mathrm{KCl}\), and \(\mathrm{O}_{2}\) gas. \(\mathrm{A}\)
\(0.415 \mathrm{g}\) sample of impure \(\mathrm{KClO}_{3}\) is heated strongly and
the \(\mathrm{O}_{2}\) gas produced by the decomposition is collected over
water. When the wet \(\mathrm{O}_{2}\) gas is cooled back to \(26^{\circ}
\mathrm{C}\), the total volume is \(229 \mathrm{mL}\) and the total pressure is
323 Torr. What is the mass percentage of \(\mathrm{KClO}_{3}\) in the original
sample? Assume that none of the impurities produce oxygen on heating. The
vapor pressure of water is 25.22 Torr at \(26^{\circ} \mathrm{C}\).