A chemist prepares a solution by adding 320 mg
of CoCl2
( MW
= 129.84 g/mol
) to a volumetric flask, and then adding water until the total volume of the contents of the flask reaches the calibration line that indicates 750 mL
. Determine the molarity of the prepared solution.
First, we need to convert the mass of CoCl2 to moles using its molar mass:
320 mg * (1 g / 1000 mg) * (1 mol / 129.84 g) = 0.00246 mol
Next, we calculate the molarity of the solution:
Molarity = moles of solute / liters of solution
Molarity = 0.00246 mol / 0.75 L = 0.00328 M
Therefore, the molarity of the prepared solution is 0.00328 M.