My science experiment showed that frozen candles burn longer, but I don't understand why. Well, let's look at what happens when candles burn.
Candles have a flammable substance like paraffin in the wax that is the fuel for the fire.
Okay, now we're getting somewhere. To make something change state, we first need to heat it to a certain temperature. So, thinking about that, if you have 2 candles, one cold and the other room temperature, and the cold wax requires more heat and a longer time to heat up and change state, then it makes sense that it would burn more slowly than the room-temperature wax. Another way to do this experiment would be with little isopropyl alcohol burners. Try the isopropyl alcohol at different temperatures and see which ones burn more quickly.