Answer:
Plug all values in equation (i)
π=1×(0.000568 mol/L)×(0.08206 Latm/molK)×298K
π=0.01389 atm
π=0.0139 atm
Therefore, the osmotic pressure of an aspirin solution is 0.0139 atm.
Step-by-step explanation:
The osmotic pressure of an aspirin solution formed by dissolving 25.0 mg of aspirin (C₉H₈O₄) in 0.250 l of water at 25°C is
The osmotic pressure is calculated as
π=i×M×R×T (i)
Where, i-van't hoff factor
M-Molarity
R=0.08206 Latm/molK
T=25°C
=25+273=298K
For a molecule C₉H₈O₄, the value of i is 1 as it is a non-electrolyte. We need to find out the molarity of the solution which is
Molarity=moles/volume in L
First calculate moles of C₉H₈O₄. The molar mass of C₉H₈O₄ is
Molar mass = [(9×12)+(8×1)+(4×16)] g/mol
=(108+8+64) g/mol
=176 g/mol
moles=25.0 mg×(1 g/1000 mg)×(1 mol/176 g)
moles=(25.0 mol/176×1000)
moles=(25.0 mol/176000)
moles=0.0001420 mol
The molarity of a solution is
Molarity(M)=0.0001420 mol/0.250 L
=0.000568 mol/L