500gm of urea solution of mole fraction 0.2 is diluted to 1500 gm. calculate the mole fraction of solute in the diluted solution
Answers
Mass of the Urea solution = 500 grams.
Molar mass of the Urea = 60 g/mole.
Mole Fraction of the Urea in a Original Solution = 0.2
This means that 0.2 mole of Urea is 1 mole solution.
∴ Mass of the Urea in a solution of 500 g = 0.2 × 60 g/mole.
= 12 g.
∴ Mass of the water = 500 - 12
= 488 g.
If the solution is diluted to 1500 gm, then only the water will be added and the amount of Urea will remains the same.
∴ Mass of the Water in a solution = 1500 - 12
= 1488 g.
∴ No. of moles of water in a solution = 1488/18
= 82.67 moles.
No. of moles of urea = 12/60
= 0.2 moles.
Total number of moles in the solution = 82.67 + 0.2
= 82.87 moles.
∴ Mole Fraction of the Solute or Urea = 0.2/82.87
= 0.0024
Hence, the Mole Fraction of the Urea in the Diluted Solution is 0.0024.
Hope it helps. :-)