A solution is prepared by dissolving 15.0 g of NH₃ in 250.0 g of water. The density of the resulting solution is 0.974 g/mL. The molarity of NH₃ in the solution is __________. A)0.00353 B)0.882 C)60.0 D)3.24 E)3.53

Question

Quizplus · Accepted Answer

First, we need to calculate the volume of the solution using its density: Density = mass/volume 0.974 g/mL = (15.0 g + 250.0 g)/volume volume = 257.0 mL Next, we need to calculate the number of moles of NH₃: moles = mass/molar mass molar mass of NH₃ = 156.06 g/mol moles = 15.0 g/156.06 g/mol moles = 0.0962 mol Finally, we can calculate the molarity of the solution: molarity = moles/volume (in liters) volume = 257.0 mL = 0.257 L molarity = 0.0962 mol/0.257 L molarity = 0.374 M Rounding to three significant figures, the molarity of the solution is 0.374 M, which corresponds to answer choice D.

A Solution Is Prepared by Dissolving 15