Question

Calculate the osmotic pressure of solution containing 0.822 gm of sucrose in 300 mL of water at 298 K.

[Given: Molar mass of sucrose 342 g/mol, R = 0.08205 dm³. atm. K⁻¹. mol⁻¹]

Answer 1

Given: Mass of sucrose (w) = 0.822 g

Molar mass of sucrose (M) = 342 g/mol

Volume of solution (V) = 300 mL = 0.300 L

Temperature (T) = 298 K

R = 0.08205 dm³. atm. K⁻¹. mol⁻¹

Number of moles of sucrose (n) = `w/M`

= `0.822/342`

= 0.0024 mol

Osmotic pressure (π) = `n/V RT`

= `0.0024/0.300 xx 0.08205 xx 298`

= 0.008 × 0.08205 × 298

= 0.1956 atm

∴ The osmotic pressure of the solution is 0.1956 atm.