What is the mole fraction of urea,CH₄N₂O,in an aqueous solution that is 37% urea by mass?

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Quizplus · Accepted Answer

The mole fraction of a component in a solution is the ratio of the moles of that component to the total moles of all components in the solution. To find the mole fraction of urea in a solution that is 37% urea by mass, we first need to calculate the moles of urea and water in a given mass of the solution, assuming a convenient total mass for the solution, such as 100 g. This makes the math straightforward: 37 g of urea and 63 g of water.The molar mass of urea (CH4N2O) is approximately 12.01 (for C) + (4*1.01) (for H) + (2*14.01) (for N) + 16.00 (for O) = 60.06 g/mol. Thus, the moles of urea in 37 g are 37 g / 60.06 g/mol ≈ 0.616 moles.The molar mass of water (H2O) is approximately 2*1.01 (for H) + 16.00 (for O) = 18.02 g/mol. Thus, the moles of water in 63 g are 63 g / 18.02 g/mol ≈ 3.496 moles.The total moles in the solution = moles of urea + moles of water = 0.616 + 3.496 ≈ 4.112 moles.The mole fraction of urea = moles of urea / total moles = 0.616 / 4.112 ≈ 0.15.

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

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