Question 27
Fill a large glass container with tap water. Add one or two drops of food colouring with a dropper. Do not stir; let the liquids mix on their own. As a class, close the windows. A student pours a teaspoon of vanilla essence into a saucer. Students at different distances across the classroom raise their hands as soon as they smell it. Explain what you think happened at the particle level for two substances to mix, for example, the food colouring and water, and the vanilla essence and air.
