Super Simple Heat Experiment

How heat affects things is sometimes difficult to understand. This simple heat experiment shows how heat causes molecules to move faster. {Plus kids think it looks cool.}

Simple Heat Experiment

Supplies you’ll need:

• 3 clear jars
• water
• food coloring
• masking tape
• markers
• thermometer {optional}

How to conduct the experiment:

1. Label the jars with the temperatures you are going to use in the experiment. We used room temperature water {about 72°F}, hot water {about 100°F}, and cold water {about 40°F}.
   
2. Turn on your sink faucet and measure the temperature. Adjust the faucet so the temperature is about 72°F. Fill the jar labeled Room Temperature. Alternatively, you can fill a jar will cool tap water and let it sit out for day. The water will eventually become the same temperature as the room.
3. Fill the jar labeled Cold Water 3/4 of the way with cold tap water. Add ice to the jar to cool the water even farther. {Or you could place this jar in the refrigerator while you wait for your Room Temperature jar to be ready.} Remove the ice from the jar before finishing your experiment.
4. An adult should help with the Hot Water jar. Turn on your faucet as hot as it will go. Fill the jar labeled Hot Water with hot water. An adult could also heat up some water on the stove. Just be careful not to make it too hot. {100°F is hot but it won’t burn skin.}
5. Add a drop of food coloring to each of the jars and observe what happens over time.

Questions to Ask:

• What happens to the drop of food coloring?
• Does the food coloring behave the same in each of the jars? Why or why not?
• What is different about the jars?
• What can you say about the relationship between heat and the movement of molecules? {for older kids}

The Science Behind It

Molecules move faster when they are warmer and slower when they are colder. The drop of food coloring spreads out fastest in the hot water because the molecules are moving the fastest of the three jars. The food coloring spreads out fairly quickly in room temperature water and slowest in the cold water. Eventually the food coloring spreads throughout all three jars.

More Simple Science Experiments

• Physics for Kids: Exploring Color and Temperature – Conduct an experiment to find out how color affects the temperature of an object. Even preschoolers can complete the steps of this experiment on their own.
• This celery science experiment is a great way to make transpiration come alive.
• Try this simple jumping experiment perfect for toddlers and preschoolers. How far can you jump?