Table 13 5 gives the vapor pressure of water at 20 0C as 2 33 x 10 3 Pa Use the ideal gas law to calculate the density of water vapor in g m 3 that would create a partial pressure equal to this vapor pressure Compare the result with the saturation vapor density given in the table Strategy To solve ...

1 Identify the knowns and convert them to the proper units a Temperature T 20C 293 K b Vapor pressur ...

Table 13.5 gives the vapor pressure of water at 20.0C as 2.33 x 10 3 Pa. Use

Question:

Table 13.5 gives the vapor pressure of water at 20.0°C as 2.33 x 10³ Pa. Use the ideal gas law to calculate the density of water vapor in g/m³ that would create a partial pressure equal to this vapor pressure. Compare the result with the saturation vapor density given in the table.

Strategy
To solve this problem, we need to break it down into a two steps. The partial pressure follows the ideal gas law,

PV = nRT, 13.70

where n is the number of moles. If we solve this equation for n/V to calculate the number of moles per cubic meter, we can then convert this quantity to grams per cubic meter as requested. To do this, we need to use the molecular mass of water, which is given in the periodic table.

Data given in Table 13.5 Temperature (C) Vapor pressure (Pa) -50 -20 -10 0 5 10 15 20 25 30 37 40 50 4.0 1.04 x 10 2.60 10 6.10 x 10