Question

What is the temperature in $°$F and the pressure in Pa at the triple point of (a) water and (b) carbon dioxide?

Short answer

(a)$T_F=32.02°F,\rho =608Pa.$

(b)$T_F=-68.8°F,\rho =5.06\times {10}^{5}Pa.$

Step-by-step solution

Description 

Figure 18.6 depicts a water diagram and triple point of water is $0.01°C$as well as the pressure is $=0.006atm$.

Includign that, Figure 18.6 depicts the diagram of carbon dioxide and triple point of carbon dioxide is $=56°C$and pressure is$=5atm$.

Result of finding the pressure and temperature 

The equation (18.6) depicts the form of

$T_F=\frac{9}{5}Tc+32°$ (1)

The value of $T_C=0.01°$is going to be used into equation (1) in order to get $T_F$

$$\begin{gathered} T_F=\frac{9}{5}Tc+32° \\ =\frac{9}{5}(0.01°)+32° \\ =32.02°F \end{gathered}$$

The next formula for calculating the pressure for Pa is:
$p=(0.006atm)\left(\frac{1.01325\times {10}^{5}Pa}{1atm}\right)=608Pa$

The value of $Tc=-56°$is going to be used into equation (1) in order to get $T_F$

$$\begin{gathered} T_F=\frac{9}{5}Tc+32° \\ =\frac{9}{5}(-56°)+32° \\ =-68.8°F \end{gathered}$$

The next formula for calculating the pressure for Pa is:
$p=(5atm)\left(\frac{1.01325\times {10}^{5}Pa}{1atm}\right)=5.06\times {10}^{5}Pa$