Question

The osmotic pressure of solution containing 34.2 g of cane sugar (molar mass = 342 g mol^-1) in 1 L of solution at 20°C is ______. (Given R = 0.082 L atm K^-1 mol^-1)

Options

• 2.40 atm

• 3.6 atm

• 24 atm

• 0.0024 atm

Answer 1

The osmotic pressure of solution containing 34.2 g of cane sugar (molar mass = 342 g mol^-1) in 1 L of solution at 20°C is 2.40 atm.

Explanation:

Osmotic pressure, π = CRT or π = `"w"/"MV"`RT

where, C = concentration of solution.

Given, w = 34.2 g, V = 1 L, M = 342 g mol^-1

T = 20° C, C = 20 + 273 = 293 °K

`therefore pi = "w"/"MV"`RT

`= (34.2 " g")/(342 " g mol"^-1) xx (0.082 " L atm K"^-1 "mol"^-1 xx 293 "K")/(1 "L")` 

= 2.40 atm.