What is the osmotic pressure of a 0.850 m solution of glucose (a non-electrolyte) in water at 35 °C? (Assume ideal behavior and use R = 0.0821 L·atm·mol^{-1}·K^{-1})

• A. 7.12 atm
• B. 0.850 atm
• C. 21.2 atm
• D. 2.05 atm

Answer: (C)

Verified step by step guidance

1. Identify the formula for osmotic pressure, which is given by \(\Pi = i M R T\), where \(\Pi\) is the osmotic pressure, \(i\) is the van't Hoff factor, \(M\) is the molarity of the solution, \(R\) is the ideal gas constant, and \(T\) is the temperature in Kelvin.
2. Since glucose is a non-electrolyte, it does not dissociate in solution, so the van't Hoff factor \(i = 1\).
3. Convert the given temperature from Celsius to Kelvin using the formula \(T(K) = T(^\circ C) + 273.15\). For 35 °C, calculate \(T = 35 + 273.15\) K.
4. Use the molality (m) given as 0.850 m to approximate the molarity (M). For dilute aqueous solutions, molality and molarity are approximately equal, so take \(M \approx 0.850\) mol/L.
5. Substitute the values into the osmotic pressure formula: \(\Pi = (1)(0.850)(0.0821)(T)\), and solve for \(\Pi\) to find the osmotic pressure in atm.