Driving question : What is the rate and order of the reaction of a solution of thiosulphate with hydrochloric acid?

In this activity students investigate the rate of reaction between thiosulphate-ions and hydrochloric acid. By using an turbidity sensor to measure the amount of light that passes through the mixture, the reaction rate can be determined. The reaction order can also be calculated from the results.

Topic: Chemical kinetics,
Concepts: Reaction order, Reaction rate,
Grade level: High School (14-18 years),
Activity type: Data logging,
Sensors: Turbidity sensor,
Interface requirements: Single analog sensor input,

The Student Worksheet gives investigation instructions for students.

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The Teacher Notes includes teacher commentaries such as didactical approach, exemplary questions, assignments and data analysis.

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The Science Background describes the scientific principles that underlie the activity.

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Coach Activity/Result file can be opened in the Coach 7 Program. This requires Coach 7 to be installed on your computer.

Download activity Rate and order of reaction (.cma7) Download result (.cmr7)