Respuesta :
Answer: The molecular weight of sucrose is 342 g/mol
Explanation:
To calculate the concentration of solute, we use the equation for osmotic pressure, which is:
[tex]\pi=iMRT[/tex]
Or,
[tex]\pi=i\times \frac{\text{Mass of solute}\times 1000}{\text{Molar mass of solute}\times \text{Volume of solution (in mL)}}\times RT[/tex]
where,
[tex]\pi[/tex] = osmotic pressure of the solution = 420.8 mmHg
i = Van't hoff factor = 1 (for non-electrolytes)
Mass of solute (sucrose) = 1.628 g
Volume of solution = 210.0 mL
R = Gas constant = [tex]62.364\text{ L.mmHg }mol^{-1}K^{-1}[/tex]
T = temperature of the solution = [tex]298K[/tex]
Putting values in above equation, we get:
[tex]420.8mmHg=1\times \frac{1.628\times 1000}{\text{Molar mass of sucrose}\times 210.0}\times 62.364\text{ L.mmHg }mol^{-1}K^{-1}\times 298K\\\\\text{molar mass of sucrose}=342g/mol[/tex]
Hence, the molar mass of the sucrose is 342 g/mol
