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: Double Ball Drop
Categories: Teacher Demonstration
A head on elastic collision between an object with mass M and an object with mass 3M traveling with equal speeds results in all the kinetic energy of the system being transferred to the smaller mass.... read more
Teacher Demo/Student Activity: Red Cabbage Indicator
Categories: Lab/Student Activity, Teacher Demonstration
This demonstration illustrates the presence and importance of chemistry in everyday objects, including our food. It is an interesting way to start the discussion of acids and bases or to connect... read more
Teacher Demo: Bright Star or Close Star?
Categories: Teacher Demonstration
When you gaze up in the night sky some stars will be very bright while other stars are barely visible to the unaided eye. With the aid of binoculars you may be able to observe different colours in... read more