What does styrofoam insulate better?

Question

Does a styrofoam cup keep cold water cold longer or hot water warm longer? If there is a difference, why would this be so?

Answer 1

NO

Styrofoam slows the transfer of energy from something warm (inside or outside) to something cold.

The difference is called 'energy gradient', and if the difference is large, the transfer will be faster. For a small gradient, the transfer will be slower, and if there is no difference, then no energy will be transferred.

While energy is being transferred, the hotter substance will get cooler, and the colder one will warm up. This reduces the energy gradient, so that the process is slowing down all the while it is happening.

Answer 2

Insulation loses heat by the difference of the temperatures on each side.

Boiling water on the inside and room temperature on the outside is a greater temeprature difference than ice water on the inside and room tem on the outside.... so it keeps cold water better than hot.... the cold water warms up more slowly than the hot water cools.