Question

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 ________ M. 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 ________ M. 3.24 0.882 3.53 0.00353 60.0

Answer 1

Answer:

[NH₃]  → 3.24 M  

Explanation:

Our solute: Ammonia

Our solvent: Water

Solution's mass = Mass of solute + Mass of solvent

Solution's mass = 15 g + 250 g = 265g

We use density to determine, the volume.

D = mass /volume → Volume = m / D →  265 g /0.974 g/mL = 272.07 mL.

We convert the mL to L → 272.07 mL . 1L /1000mL = 0.27207 L

To determine molarity we need the moles of solute in 1 L of solution.

Moles of solute are: 15g / 17g/mol = 0.882 moles

[NH₃] = 0.882mol /0.27207 L → 3.24 M