EXPERIMENT: USING THE TYNDALL EFFECT TO IDENTIFY COLLOIDS

These supplies are needed:

3 clear glasses with smooth sides
laser pointer or flashlight
red Jell-O
red food coloring
sugar
water
Procedure:

Using the regular recipe, mix up the Jell-O and fill one glass with the mixture. Let chill until it gels. Fill another glass with water and let settle until the air bubbles disperse. Fill the third glass with water and add 2 drops of food coloring and two tablespoons of sugar into the water in the third glass. Stir until you are sure the sugar is completely dissolved.

When all three glasses are ready, line them up in any order and shine the laser (or flashlight) through all three glasses at the same time.

Answer these questions:

What did you observe?
What is the Tyndall effect?
Which glass displayed the Tyndall effect?
What does that tell you about the substance in the glass?
Which glass represents a pure substance?
Which glass represents a solution?