List of states of matter

Classically, states of matter are distinguished by changes in specific heat capacity, pressure and temperature. States are distinguished by a discontinuity in one of those properties: for example, raising the temperature of ice produces a clear discontinuity at 0°C as energy goes into phase transition, instead of temperature increase.

In the 20th century, increased understanding of the more exotic properties of matter has resulted in many additional states of matter, none of which are observed in normal conditions.

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