Question

the Osmotic pressure of 0.010 M solution of kI and sucrose our 0.432 atm and 0.24 atm respectively. the van't Hoff factor for KI is​

Answer 1

GIven:

The molarity of KI and sucrose solutions, C = 0.01 M

The osmotic pressure of KI solution, Π (KI) = 0.432 atm

The osmotic pressure of sucrose solution, Π (sucrose) = 0.24 atm

To Find:

The Van’t Hoff factor, i.e., 'i' for Potassium Iodide.

Calculation:

- Sucrose is a non - electrolyte compound, so it does not dissociate in water.

- The osmotic pressure of sucrose is given as:

Π(sucrose) = C × R × T

⇒ 0.24 = 0.1 × R × T

⇒ R × T = 2.4 ....(i)

- As KI dissociates in water to form K⁺ and I⁻.

- The osmotic pressure of KI can be given as:

Π (KI) = i × C × R × T

⇒ 0.432 = i × 0.1 × 2.4     {from (i)}

⇒ i = 0.432/0.24

⇒ i = 1.8

- So, the Van’t Hoff factor for KI is 1.8.