Rate of Reaction of Sodium Thiosulfate and Hydrochloric Acid

The purpose of this demonstration is to investigate the effect of sodium thiosulfate concentration on the rate of reaction of sodium thiosulfate with hydrochloric acid. The reaction, which produces solid sulfur, will be followed by measuring the time needed for the reaction mixture to become opaque. The results will be analyzed graphically to determine the order of reaction— the mathematical relationship between the reactant concentration and the rate.