Ouch - Hot Pizza!When eating pizza the recently with my family, my wife and I burned the roof of our mouth's as so many people do. The next time we had pizza we waited several minutes before chowing down. While waiting my son was asking why the crust did not feel hot while the cheese was very steamy even after several minutes. A great question!
I immediately proceeded in giving some long-winded explanation to an 8-year old about the heat capacity of cheese being higher than the heat capacity of the crust. Of course I had to explain that heat capacity (C) is amount of heat energy (q) needed to raise the temperature (Δ T) of a specific amount of substance (mass, m).
The formula: q = C × m × (Δ T)
The higher the Heat Capacity the longer it stays hot. In addition, bread is a good insulator so it transfers heat very slowly while mozzarella cheese being a better conductor transfers heat faster.
After after giving this explanation I asked my son if he understood, to which he replied, "Oh I got it, the crust has lots of holes in it like bread or bubbles which means it won't get as hot". His explanation is essentially correct (replace get as hot with hold as much heat) and is simpler to understand than mine. The crust is much less dense than the cheese, thus the same volume of cheese can hold a lot more heat than the same volume of crust. In think I will run explanations through him from know on.
Believe it or not, others have studied this topic. For more information checkout: The Thermodynamics of Pizza from ChemPRIME.