#"Molarity"# #=# #"Moles of solute"/"Volume of solution"#, and thus #"molarity"# has units of #mol*L^-1#. And thus,
#"Moles of solute"="Volume of solution"xx"molarity"#
We have a #2"mM"# solution, i.e. a #2.0xx10^-3mol*L^-1# of #CaCl_2#, and, clearly, there are #2.0xx10^-3mol# of #CaCl_2# present in solution.
Thus, with respect to #CaCl_2# there are ............
#1*cancelLxx2.0xx10^-3cancel(mol*L^-1)xx110.98*g*cancel(mol^-1)# #=# #0.222*g# calcium chloride. What is the concentration of this solution with respect to #Cl^-# ion?