Thermodynamics

Thermodynamic anomalies of water -- unusual compressibility, heat capacity, heat of vaporization, and thermal conductivity.

Advanced Locked #27

Water has an unusually low compressibility

Despite being a liquid, water is harder to compress than many other liquids.

Advanced Locked #28

Compressibility decreases with rising temperature up to 46.5 degrees Celsius

For most liquids, compressibility increases with temperature -- for water it initially decreases.

Advanced Locked #29

There is a maximum in the compressibility-temperature relationship

The isothermal compressibility shows a maximum at low temperatures.

Advanced Locked #30

The speed of sound increases with temperature up to 74 degrees Celsius

In most liquids, the speed of sound decreases with temperature -- in water it increases.

Advanced Locked #31

The speed of sound may exhibit a minimum

Under certain conditions, the speed of sound in water exhibits a minimum.

Advanced Locked #32

Fast sound occurs at high frequencies and shows a discontinuity at higher pressure

At high frequencies, sound propagates faster in water, with a jump at high pressure.

Advanced Locked #55

The heat of melting of water has a maximum at -17 degrees Celsius

The heat of melting shows a maximum at supercooled temperatures rather than at the normal melting point.

Accessible Locked #56

Water has more than twice the specific heat capacity of ice or steam

The specific heat of liquid water is anomalously high compared to its solid and gaseous phases.

Advanced Locked #57

The specific heat capacity (Cp and Cv) is unusually high

Both at constant pressure and constant volume, the heat capacity of water is unusually large.

Advanced Locked #58

The specific heat capacity Cp has a minimum at 36 degrees Celsius

The heat capacity at constant pressure passes through a minimum near body temperature.

Advanced Locked #59

The specific heat capacity Cp has a maximum at approximately -45 degrees Celsius

In the supercooled range, Cp increases dramatically and shows a maximum.

Advanced Locked #60

The specific heat capacity Cp has a minimum with respect to pressure

The pressure dependence of Cp shows an unusual minimum.

Advanced Locked #61

The heat capacity Cv has a maximum

The isochoric heat capacity shows a maximum at a certain temperature.

Accessible Locked #62

Water has a high heat of vaporization

The heat of vaporization of water is one of the highest of all liquids.

Advanced Locked #63

Water has a high heat of sublimation

The energy required to convert ice directly into vapor is unusually high.

Advanced Locked #64

Water has a high entropy of vaporization

The entropy of vaporization of water deviates significantly from Trouton's rule.

Advanced Locked #65

The thermal conductivity of water is high and reaches a maximum at 130 degrees Celsius

The thermal conductivity of liquid water is high and shows a maximum at elevated temperature.