Answer to Question #315674 in Inorganic Chemistry for Qybb

Question

Determine the osmotic pressure of the solution made by dissolving 25.0 g of sodium chloride in 2.0 L of solution at 25 0C.

Answer 1

m(NaCl) = 25.0 g;

M(NaCl) = 58.5 g/mol;

V(solution) = 2.0 L;

T = 25 C = 298 K;

R = 8.314 (L * kPa/(K * mol));

$\pi$ = i * C * R * T;

NaCl = Na⁺ + Cl-;

Therefore, for follow reaction i = 2;

C = n(NaCl)/V(solution) = m(NaCl)/(M(NaCl) * V(solution)) = 25/(58.5 * 2) = 25/117 = 0.2137 mol/L;

Then,

$\pi$ = 2 * 0.2137 * 8.314 * 298 = 1058.9 kPa = 10.4 atm.

Answer: 1058.9 kPa or 10.4 atm.