Question

Commercial concentrated aqueous ammonia is 28% NH₃ by mass and has a density of 0.90 g/mL. What is the concentration of ammonia in molarity?

A) 14.82 M
B) 28.00 M
C) 12.00 M
D) 16.00 M
E) 17.00 M

Answer 1

To find the concentration of ammonia in molarity, we first need to calculate the number of moles of NH₃ in the solution. The density of the solution can be used to find the volume of the solution, and then by using the molar mass of ammonia, we can find the number of moles. Using the given information, we can calculate the concentration of ammonia in molarity to be approximately 14.82 M (option A).

Step-by-step explanation:

To find the concentration of ammonia in molarity, we first need to calculate the number of moles of NH₃ in the solution. The density of the solution can be used to find the volume of the solution, and then by using the molar mass of ammonia, we can find the number of moles.

First, let's calculate the volume of the solution:

Volume = mass / density = (28% * mass of solution) / (density of solution)

Next, let's calculate the number of moles of NH₃:

Moles of NH₃ = (mass of NH₃ / molar mass of NH₃)

Finally, let's calculate the concentration in molarity:

Molarity = (moles of NH₃ / volume of solution)

Using the given information, we can calculate the concentration of ammonia in molarity to be approximately 14.82 M (option A).