Heat produces protective vapour
An insulating water vapour cushion makes small water drops hover above the pot bottom at a temperature of 200° – without evaporating.
Every child knows that water will boil and evaporate at a temperature of 100° C (or slightly less if you live at high altitude). But what happens, at extreme temperatures? Then you will prevent the water from evaporating, and instead, the water drops remain intact, skittering about.
This is due to the Leidenfrost effect, which can be observed quite simply, using just water, a hotplate, and a pot.
At a temperature of just over 200°C, the Leidenfrost point is reached. The point is the optimum temperature above the boiling point of water to keep drops intact. At this temperature, a cushion of vapour will be produced in the contact area between the hotplate and the water drop. The cushion will make the drop hover immediately above the bottom of the pot, suspended like a steampunk hoverboard..
It works, because steam is a poorer conductor of heat than liquid water, so the water of the drop is not affected by the intense heat from the hotplate.