Experiences

Experiments offer palpable demonstrations which involve students

Mihaela Ciocan

Romania

High Secondary School

Biology

Teaching in class

Direct

Experiments offer palpable demonstrations which involve students. They encourage independent learning and empower students to assume responsibilities. The following experiment is great for testing if hot water molecules really move faster than cold ones. Pour some water, drop in some food coloring and compare results. What you need is: a glass with hot water; a glass filled with cold water; food coloring and an eye dropper. Ask students to fill the glasses with the same amount of water, one cold and one hot. Then they have to put one drop of food coloring into both glasses as quickly as possible. The most exciting part is now: they have to watch what happens to the food colouring. If you watch closely you will notice that the food coloring spreads faster throughout the hot water than in the cold. The molecules in the hot water move at a faster rate, spreading the food coloring faster than the cold water molecules which mover slower.