In this demonstration, a chemical reaction is used to make a hidden message visible. The demonstration illustrates an entertaining application of chemical reactions in toys and everyday objects. It is also an interesting way to start the discussion of acids and bases, the pH scale, or acid-base indicators. Invisible ink has been used in espionage to send messages that cannot easily be read by enemies.
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Teacher Demo/Student Activity: Bending Water
Categories: Lab/Student Activity, Teacher Demonstration
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Teacher Demo: Toxic Path: Bioaccumulation
Categories: Teacher Demonstration
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Teacher Demo: Limiting Reagent - Is More Better?
Categories: Lab/Student Activity, Teacher Demonstration
This demonstration/activity introduces students to the concept of limiting reagent in a chemical reaction. Too often, students think that one can produce more product by using larger quantities of... read more