A dilute solution of an ionic compound A ₃ ~B has an Osmotic pressure which is 6 times that of 0.02 M MgCl ₂ . What is the molar concentration of A ₃ ~B assuming that it undergoes complete dissociation in water?

Step-by-step solution

The osmotic pressure is given by the formula = iCRT , where i is the van't Hoff factor, C is the molar concentration, R is the gas constant, and T is the temperature. For MgCl ₂ , which dissociates as MgCl ₂ Mg ²⁺ + 2 Cl ⁻ , the van't Hoff factor i₁ = 1 + 2 = 3 . The concentration C₁ = 0.02 M . Thus, ₁ = 3 0.02 RT = 0.06 RT . For A ₃ B , which dissociates as A ₃ B 3 A ⁺ + B ³⁻ , the van't Hoff factor i₂ = 3 + 1 = 4 . Let the concentration be C₂ . Thus, ₂ = 4 C₂ RT = 4 C₂ RT . Given that ₂ = 6 ₁ , we substitute the