Question

What is the molarity of $0.060$ mol of $NaHC{O_3}$ in $1500$ ml of solution?

Answer 1

Hint : Molarity is a term used to find the concentration of the solute in the given solution. So, molarity can be defined as the number of moles of solute present per litre of the solution. It is one of the most common terms to determine concentration of the solutes.

Complete Step By Step Answer:
As we know that molarity is the $\dfrac{{moles}}{{litre}}$ of the solution.
To find the molarity of the given solution, we should know the number of moles of the solute that are present in the given solution and the total volume of the solution.
Here, the most important point to keep in mind is that here we are taking into consideration the total volume of the solution and not the volume of the solvent.
So, let’s have a look at the formula to calculate molarity:
$\Rightarrow Molarity= \dfrac{{{\text{Number of moles of solute}}}}{{{\text{Volume of the solution (in litres)}}}}$
$\Rightarrow$ $M = \dfrac{n}{V}$
So, in the question we are given,
Number of moles of sodium bicarbonate, $NaHC{O_3}$ $=$ $0.060$ mole
Total volume of the solution $=$ $1500$ ml
Important point to note here is that the volume is given in millimeters but we need the volume in litres.
So, we will divide the $1500$ ml by $1000$ , thus, we get:
V $=$ $1.5L$
Now, putting these values in the above formula:
Molarity $=$ $\dfrac{{0.060}}{{1.5}}$
$\Rightarrow$ $M = 0.04{\text{ mole litr}}{{\text{e}}^{ - 1}}$
Thus, the molarity of $0.060$ mol of $NaHC{O_3}$ in $1500$ ml of solution is $0.04{\text{ mole litr}}{{\text{e}}^{ - 1}}$ .

Note :
Molarity of the solution depends on the temperature of the solution also. This is because the molarity depends on the volume of the solution, as we have just seen above in the formula. So, it is very important to maintain the correct temperature of the solution while measuring the molarity of the solution.