Calculate the percent by mass of potassium nitrate in a solution made from 45.0 g KNO₃ and 295 mL of water. The density of water is 0.997 g/mL. A) 1.51 % B) 7.57 % C) 13.3 % D) 15.2 % E) None of these

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Quizplus · Accepted Answer

First, we need to calculate the total mass of the solution: mass of solution = mass of solute + mass of solvent mass of solution = 45.0 g KNO₃ + (295 mL x 0.997 g/mL) water mass of solution = 45.0 g KNO₃ + 293.865 g water mass of solution = 338.865 g Next, we need to calculate the mass of potassium nitrate in the solution: mass of KNO₃ in solution = 45.0 g KNO₃ Finally, we can calculate the percent by mass of potassium nitrate in the solution: percent by mass = (mass of KNO₃ in solution / mass of solution) x 100% percent by mass = (45.0 g / 338.865 g) x 100% percent by mass = 13.3% Therefore, the answer is C: 13.3%.

Calculate the Percent by Mass of Potassium Nitrate in a Solution