Answer : The correct option is, (b) 0.087
Explanation :
The formula used for relative saturation is:
[tex]\text{Relative saturation}=\frac{P_A}{P_A^o}[/tex]
where,
[tex]P_A[/tex] = partial pressure of ethyl acetate
[tex]P_A^o[/tex] = vapor pressure of ethyl acetate
Given:
Relative saturation = 50 % = 0.5
Vapor pressure of ethyl acetate = 16 kPa
Now put all the given values in the above formula, we get:
[tex]0.5=\frac{P_A}{16kPa}[/tex]
[tex]P_A=8kPa[/tex]
Now we have to calculate the molar saturation.
The formula used for molar saturation is:
[tex]\text{Molar saturation}=\frac{P_{vapor}}{P_{\text{vapor free}}}[/tex]
and,
P(vapor free) = Total pressure - Vapor pressure
P(vapor) = [tex]P_A[/tex] = 8 kPa
So,
P(vapor free) = 100 kPa - 8 kPa = 92 kPa
The molar saturation will be:
[tex]\text{Molar saturation}=\frac{P_{vapor}}{P_{\text{vapor free}}}[/tex]
[tex]\text{Molar saturation}=\frac{8kPa}{92kPa}=0.087[/tex]
Therefore, the molar saturation is 0.087
