Which material is best for keeping water hot?

Apparatus list:

Two copper cans
Boiling water
Stopwatch
Two measuring cylinders
Cotton
Corrugated cardboard
Two thermometers
Sellotape

Diagram:













Prediction:

We predict that the corrugated card will be the best insulator. We predict this because corrugated cardboard has pockets of air inside it and for heat to travel through air, convection needs to take place. It is harder for convection take places than it is for conduction to take place.
The reason that convection is harder than conduction is that the particles in a gas is far apart from each other and need to vibrate a lot before they begin to hit each other. However, the particles in a solid are very close together in a pattern and as the particles begin to heat up, they vibrate and hit each frequently and the heat is conducted through the material.
So, the corrugated card has the ability to keep warmth in whereas cotton does, but not as well as the cardboard.


Fair Test:

To make ...