Question

What is the concentration of ammonia in a solution made by dissolving 3.75 g of ammonia in 120.0 l of water?

Answer 1

Answer: The concentration of ammonia is 0.00184 M

Step-by-step explanation:

To calculate the molarity of solution, we use the equation:

`\text{Molarity of the solution}=\frac{\text{Mass of solute}}{\text{Molar mass of solute}* \text{Volume of solution (in L)}}`

We are given:

Mass of solute (ammonia) = 3.75 g

Molar mass of ammonia = 17 g/mol

Volume of solution = 120.0 L

Putting values in above equation, we get:

`\text{Concentration of ammonia}=(3.75g)/(17g/mol* 120.0L)\\\\\text{Concentration of ammonia}=0.00184M`

Hence, the concentration of ammonia is 0.00184 M

Answer 2

Below are the choices that can be found elsewhere:

a) 7.05 M
b) 3.78×10^−2 M
c)1.84×10^−3 M
d)0.0313 M
e)1.84 M

Below is the answer:

mol = mass/m.wt = 3.75/17.03 = 0.22 mol
Molarity = mol / Volume(L) = 0.22/120.0 = 1.84 * 10^-3
c)1.84×10^−3 M