Science Buddies: "Ask an Expert"

I am investigating what shape of chocolate will melt fastest, and I need to research some background information. I was wondering how heat affects objects of different shapes? I think that even if I am melting the same quantity of chocolate, it will melt at a different rate if the shape is a triangle or diamond vs. a square or circle, but I'm not sure why.
- Rachael

You will discover that the "temperature" at which your chocolate melts will always be the same, regardless of the shape. I would suggest you get an inexpensive infrared temperature measuring gun and keep track of the temperature of the surface of your samples. As long as they are made from the same chocolate, they will melt at the same temperature.

Once your chocolate begins to melt, the quantity of chocolate will determine how long it takes. Large shapes will take longer than small shapes.

However, the shape can affect the temperature - it depends on how you apply the heat. If you apply the heat with a heat lamp, a shape that is broad might reach its melting temperature than a shape that is narrow. If you put your shapes in a sauce pan to melt, the one with the largest bottom might absorb heat faster and get to it's melting point sooner.

You should try several shapes and see what you learn. Remember, find some way to measure the temperature of the chocolate, and try to apply the heat in the same way for each sample.

Good luck, and have fun!