Light Transmission through a Precipitate

Light shield

Sodium thiosulfate and hydrochloric acid react in conical flask

The transmission of light through the reaction mixture is measured using a datalogger and light sensor

As the sulfur precipitate gradually forms, the solution becomes cloudier

The amount of light transmitted is a measurement of the reaction's progression

Measure and record the time taken for the light intensity to drop to a minimum value

Calculate the rate of reaction by calculating 1/reaction time

Light source transmits light through reaction mixture