80

70

60

10

0

10

20

30

50

40

Temperature (C)

The heat capacity of liquid water can be calculated accurately from the equation of state

for liquid water. The equation-of-state models for water are comprehensive and algebra-

ically complex. Fortunately, there are several computer programs available (Harr et al.

1976, Hill 1990) that can be used to calculate accurately the thermodynamic properties,

including heat capacity.

As noted above, Speedy (1987) has presented equations for the various thermodynamic

properties of supercooled water. His expression for the constant-pressure heat capacity of

supercooled water is

(

(10)

The regression estimates of these parameters are presented in Table 1. Figure 7 presents the

isobaric heat capacity of water as calculated by the models of Hill (1990) and Speedy (1987).

250

200

150

100

50

60

40

20

0

20

40

Temperature (C)

9

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