What is the mole fraction of urea,CH₄N₂O,in an aqueous solution that is 54% urea by mass? A) 0.26 B) 0.74 C) 0.54 D) 0.37 E) 0.80

Question

Quizplus · Accepted Answer

To find the mole fraction, we need to know the moles of urea and moles of water present in the solution. Let's assume we have 100 g of this solution, which means 54 g of urea and 46 g of water.

The molar mass of urea is 60 g/mol. Therefore, the moles of urea present in 54 g is:

moles of urea = (54 g) / (60 g/mol) = 0.9 mol

The molar mass of water is 18 g/mol. Therefore, the moles of water present in 46 g is:

moles of water = (46 g) / (18 g/mol) = 2.56 mol

The total moles of the solution is the sum of the moles of urea and water:

total moles = 0.9 mol + 2.56 mol = 3.46 mol

Now, the mole fraction of urea is:

mole fraction of urea = moles of urea / total moles = 0.9 mol / 3.46 mol = 0.26

Therefore, the answer is A) 0.26.

What Is the Mole Fraction of Urea,CH4N2O,in an Aqueous Solution

What Is the Mole Fraction of Urea,CH₄N₂O,in an Aqueous Solution