19.99 g CaCl
This is a dilution problem. The equation for dilution is:
You're given the mass of calcium chloride and the volume of solution. The first step is to find the amount of moles of CaCl that you have. Using dimensional analysis you can solve.
Now we find the molarity by dividing the moles of CaCl by the volume of solution given in the question. Convert the solution into liters, as it's the units you will need to finish the problem.
This is the
Rearranging using some algebra we get
Now that we have moles of CaCl we can convert into required mass.