Mercury(II) iodide is heated to convert it from its red low-temperature alpha form to its yellow high-temperature beta form.
When the beta form of mercury(II) iodide cools to below the transition temperature of 126°C, it returns to the red/orange alpha form.
When memory metal is bent, it deforms. When placed into hot water, the metal "remembers" its original shape.
An animation illustrates how peeling occurs between layers where bonding is weak in molybdenum disulfide.
Butter is used to glue a piece of pasta to each disk. When the edges of the disks are immersed in hot water, the butter on the diamond melts more rapidly, releasing the piece of pasta.
A synthetic diamond wafer and an aluminum disk are held between a thumb and forefinger (to provide heat). When pressed against an ice cube, the diamond penetrates more rapidly than does the aluminum.