Question

If you had 0.867 miles of salt, NaCI , in a 0.69 L solution, what would be the molarity

Answer 1

Approximately
`1.3\; \rm mol \cdot L^(-1)`. (Assuming that the question says
`0.867` moles of salt in this
`0.69\; \rm L` solution.)

Step-by-step explanation:

The molarity of a solution gives the quantity of the solute in every unit volume of the solution. In this question:

• Quantity of solute:
  `n(\text{solute})= 0.867\; \rm mol` (with moles as the unit.)
• Volume of solution:
  `V(\text{solution}) = 0.69\; \rm L` (with liters as the unit.)

Note that in this question, liter is the unit for the volume of the solution. The molarity of the solution should thus give the amount of solute in every liter of the solution:

`\begin{aligned} c & = \frac{n(\text{solute})}{V(\text{solution})} \\ &= (0.867\; \rm mol)/(0.69\; \rm mol) \approx 1.3\; \rm mol \cdot L^(-1)\end{aligned}`.