Most Important Selected Qs for JEE AdvancedChemistrySolutions
If the sum of mole fraction of NaOH in its aqueous solution and the mole fraction of H ₂ O in an another aqueous solution of KOH is equal to one, find the molality of KOH solution if the molality of NaOH solution is ' m '. Report your answer as ' Y ' where Y = (Molality of KOH solution) (Molality of NaOH solution)
Correct answer
1
Step-by-step solution
Let mole fraction of NaOH in its aqueous solution be X . Mole fraction of H ₂ O in an aqueous solution of KOH =1- X so, mole fraction of KOH in its aqueous solution =1-(1-X)=X Thus, both aqueous NaOH solution and aqueous KOH solution have same mole fraction of solute. Now, molality = X _ solute 1000 (1- X _ solute ) Mol.Mass _ solvent Since both solutions have same solvent ( H ₂ O ) and same mole fraction of solute, so they will have same molality Molality of aq. KOH solution = m Y=m / m=1