Chocolate melts at a certain temperature causing a physical change as a solid turns into a liquid. The following is a good experiment to carry out when studying the physical states of matter. Students can expose chocolate to different conditions and temperatures in order to determine the melting point of the chocolate, the time required to melt the chocolate depends on the conditions of the experiment and type of chocolate. Remember to record the results to compare them and come to a conclusion.
Place each piece of chocolate on a paper plate. Put one of them outside in a shady place and write down the temperature the chocolate is exposed to. Start the timer.
Observe the chocolate and stop the timer when the chocolate begins to melt. Register the period of time that elapsed before the chocolate reached melting point. Record the level of softness of the chocolate after 10 minutes if the weather is not warm enough for the chocolate to melt.
Repeat steps 1 and 2, but this time place the chocolate directly in the sun. Record the outcome of the test and compare temperatures and time. Give the experiment a twist by placing the chocolate on an aluminium foil sheet and observe temperature or time changes. Record and measure the similarity or difference between both situations.
Think of more appealing locations to put the chocolate pieces and register the results. Try placing the chocolate in hot water, into your own mouth or into a pocket for instance. Record the results again.
Practice now with different types of chocolate, comparing dark chocolate and white chocolate. Do not forget to take note of the results.
Compare notes with the rest of the class and try to reach a conclusion. Answer questions like what conditions are ideal for chocolate to melt, what temperature does chocolate melt at, or what type of chocolate is more susceptible to high temperature melting points?
You can also test the experiment in reverse to study solidification, which is the process that turns a fluid into a solid. Just put the melted chocolate into the freezer or the fridge and monitor the time it takes to reach freezing point.
Chocolate stains are hard to remove. You should cover the working surface with newspapers. You can also use gloves so you don't mess on your hands or clothes. Wrap the chocolate in plastic if you decide to test it in your pocket or your school bag.