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Iodine Clock Challenge—General, Organic and Biological Chemistry Kit

By: The Flinn Staff

Item #: AP8027

Price: $54.60

In Stock.

General, Organic and Biological Chemistry (GOB) Lab Kit: Iodine Clock Challenge lets you observe the iodine clock reaction, analyze how the concentration of potassium iodate influences the rate of the reaction, and more.

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This item can only be shipped to schools, museums and science centers

Product Details

General, Organic and Biological Chemistry The demonstration of an “iodine clock” involves a chemical reaction that suddenly turns blue due to the formation of the familiar iodine–starch complex. The color change occurs abruptly, like an alarm clock ringing. Can students predict the amount of time it will take for the iodine clock to ring? This guided-inquiry activity allows students the opportunity to observe the iodine clock reaction, analyze how the concentration of potassium iodate influences the rate of the reaction, and then predict the amount of potassium iodate needed to make the clock “ring” in 25 seconds and verify the accuracy of their prediction. Complete for 24 students working in pairs.


Materials Included in Kit: 
Potassium iodate, lab grade, 100 g
Sodium meta-bisulfite, 25 g
Soluble potato starch, 30 g
Cup, clear plastic, tall, 10 oz, 60

Correlation to Next Generation Science Standards (NGSS)

Science & Engineering Practices

Asking questions and defining problems
Developing and using models
Planning and carrying out investigations
Analyzing and interpreting data
Engaging in argument from evidence
Obtaining, evaluation, and communicating information
Using mathematics and computational thinking

Disciplinary Core Ideas

MS-PS1.B: Chemical Reactions
HS-PS1.B: Chemical Reactions

Crosscutting Concepts

Cause and effect
Scale, proportion, and quantity
Systems and system models
Energy and matter

Performance Expectations

MS-PS1-1. Develop models to describe the atomic composition of simple molecules and extended structures.
MS-PS1-2. Analyze and interpret data on the properties of substances before and after the substances interact to determine if a chemical reaction has occurred.
HS-PS1-1. Use the periodic table as a model to predict the relative properties of elements based on the patterns of electrons in the outermost energy level of atoms.
HS-PS1-2. Construct and revise an explanation for the outcome of a simple chemical reaction based on the outermost electron states of atoms, trends in the periodic table, and knowledge of the patterns of chemical properties.
HS-PS1-5. Apply scientific principles and evidence to provide an explanation about the effects of changing the temperature or concentration of the reacting particles on the rate at which a reaction occurs.