Determine the osmotic pressure of a solution prepared by dissolving 25 mg of K 2 SO 4 in 2 litre of water at 25° C, assuming that it is completely dissociated.

Question

Philoid · Accepted Answer

Given-

Mass of K₂SO₄, w = 25 mg = g,

Molar mass of K₂SO₄ = (39×2) + (32×1) + (16×4) = 174 g mol^-1

Volume V = 2 liter

T = 25⁰C + 273 = 298 K (add 273 to convert in Kelvin)

The reaction of dissociation of K₂SO₄ is written as,

K₂SO₄ → 2K ⁺ + SO₄^2-

Number if ions produced = 2 + 1 = 3, hence vant Hoff’s factor, i = 3

Here, we use vant Hoff’s equation for dilute solutions, given as,

→

where, n is the number of moles of solute, R is solution constant which is equal to the gas constant(0.082) and T is the absolute temperature (298 K).

Hence, the osmotic pressure of a solution is 5.27x10^-3atm

Determine the osmotic pressure of a solution prepared by dissolving 25 mg of K2SO4 in 2 litre of water at 25° C, assuming that it is completely dissociated.

Determine the osmotic pressure of a solution prepared by dissolving 25 mg of K₂SO₄ in 2 litre of water at 25° C, assuming that it is completely dissociated.