Question

An artificial cell is made by encapsulating $0.2 \, \text{M}$ glucose solution within a semipermeable membrane. The osmotic pressure developed when the artificial cell is placed within a $0.05 \, \text{M}$ solution of NaCl at 300 K is ______ $\times 10^{-1} \, \text{bar}$. (Nearest Integer)
Given: $R = 0.083 \, \text{L bar mol}^{-1} \text{K}^{-1}$
Assume complete dissociation of NaCl.

Answer 1

For NaCl dissociation:
$\text{NaCl} \rightarrow \text{Na}^+ + \text{Cl}^-$
Concentration of NaCl = 0.05 M.
Effective concentration ($C_1$) = 0.05 M + 0.05 M = 0.1 M.
Glucose concentration ($C_2$) = 0.2 M.
The osmotic pressure:
$\pi = (C_2 - C_1)RT$

Substituting:
$\pi = (0.2 - 0.1) \times 0.083 \times 300 = 24.9 \times 10^{-1} \, \text{bar}$
Nearest integer = 25 bar.