IB Chemistry HL 1.5.4 Ideal Gas Equation Question Bank

A group of students investigated the rate of the reaction between aqueous sodium thiosulfate and hydrochloric acid according to the equation below.

The two reagents were rapidly mixed together in a beaker and placed over a mark on a piece of paper. The time taken for the precipitate of sulfur to obscure the mark when viewed through the reaction mixture was recorded.

Initially they measured out $10.0 \mathrm{~cm}^{3}$ of $0.500 \mathrm{moldm}^{-3}$ hydrochloric acid and then added $40.0 \mathrm{~cm}^{3}$ of $0.0200 \mathrm{~mol} \mathrm{dm} \mathrm{m}^{-3}$ aqueous sodium thiosulfate. The mark on the paper was obscured 47 seconds after the solutions were mixed.

Another group suggested collecting the sulfur dioxide and drawing a graph of the volume of gas against time.

Calculate the volume of sulfur dioxide, in $\mathrm{cm}^{3}$, that the original reaction mixture would produce if it were collected at $1.00 \times 10^{5} \mathrm{~Pa}$ and 300 K .