Question

A 2400.-gram sample of an aqueous solution contains 0.012 gram of nh3. What is the concentration of nh3 in the solution

Answer 1

Answer : The concentration of $NH_3$ in the solution is, $2.94\times 10^{-4}M$

Explanation :

First we have to calculate the volume of aqueous solution that is water.

Density of water = 1.00 g/mL

Mass of water = 2400 g

$\text{Volume of water}=\frac{Mass}{Density}=\frac{2400g}{1.00g/mL}=2400mL$

Now we have to calculate the concentration of ammonia solution.

Molarity : It is defined as the number of moles of solute present in one liter of volume of solution.

Formula used :

$\text{Molarity}=\frac{\text{Mass of }NH_3\times 1000}{\text{Molar mass of }NH_3\times \text{Volume of solution (in mL)}}$

Molar mass of $NH_3$ = 17 g/mole

Now put all the given values in this formula, we get:

$\text{Molarity}=\frac{0.012g\times 1000}{17g/mole\times 2400mL}=3.12mole/L=2.94\times 10^{-4}M$

Therefore, the concentration of $NH_3$ in the solution is, $2.94\times 10^{-4}M$