What are 10 rare examples of reversible changes?

Reversible changes are processes that allow a substance to return to its original state. Examples include the melting of ice into water, which can freeze back into ice; the boiling of water into steam, which can condense back to liquid; and dissolving sugar in water, which can be reversed by evaporation. Other examples include the stretching of rubber, the folding of paper, the magnetization of certain metals, the expansion of gases when heated, the mixing of sand and salt, and the transformation of wax when heated and cooled.