Brine (saturated aqueous NaCl solution) is often used in extraction procedures. The concentration of a saturated brine at room temperature is 358 g of NaCl in 1.00 L of water. Calculate the molarity and density of saturated brine (do not forget that brine is NaCl + H2O). What is the density (g/mL)?
To calculate the molarity of NaCl in the saturated brine solution, we need to find the number of moles of NaCl present in the solution.
The molar mass of NaCl is 58.44 g/mol.
We are given that the concentration of NaCl in saturated brine is 358 g/L. Therefore, the number of moles of NaCl is:
Number of moles = mass/molar mass
Number of moles = 358 g/ 58.44 g/mol = 6.13 mol
Since the volume of the solution is 1.00 L, the molarity of NaCl in the solution is:
Molarity = Number of moles/volume of solution
Molarity = 6.13 mol/ 1.00 L = 6.13 M
The density of the saturated brine can be calculated by dividing the mass of the solution by its volume.
The mass of 1.00 L of saturated brine is 358 g (given).
Therefore, the density is:
Density = mass/volume
Density = 358 g/ 1.00 L = 358 g/L
However, the density is typically expressed in g/mL. To convert g/L to g/mL, we divide by 1000.
Density = 358 g/L ÷ 1000 = 0.358 g/mL
So, the density of the saturated brine is 0.358 g/mL.