What is the mole fraction of urea,CH₄N₂O,in an aqueous solution that is 49% urea by mass? A) 0.22 B) 0.78 C) 0.49 D) 0.42 E) 0.76

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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, we first calculate the moles of urea and water in a given mass of solution, assuming 100 g for simplicity. Urea (CH4N2O) has a molar mass of approximately 60 g/mol, so 49 g of urea is 49 g / 60 g/mol = 0.817 moles of urea. Water has a molar mass of 18 g/mol, so 51 g of water is 51 g / 18 g/mol = 2.833 moles of water. The total moles in the solution is 0.817 + 2.833 = 3.65 moles. The mole fraction of urea is then 0.817 moles / 3.65 moles = 0.224, which rounds to 0.22.

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

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