#60# #mL# of a #1.5# #M# solution of #HCl# is diluted to a volume of #2.0# #L#. What is the concentration of the new solution?

1 Answer
May 21, 2017

Step 1: #n = CV = 1.5xx0.060 = 0.09# #mol#

Step 2:
#C = n/V = 0.09/2 = 0.045# #molL^-1#

Explanation:

The solution to this is a two-step process: finding the number of moles of HCl in the initial solution, then calculating the concentration of the final solution.

We will use the equation #C = n/V# in both steps.

#C# is the concentration in #molL^-1# (also called #M#), #n# is the number of moles of solute and #V# is the volume of the solution in #L#.

For step 1, rearrange to make #n# the subject:

#n = CV = 1.5xx0.060 = 0.09# #mol# (changing the volume from #mL# to #L#)

For step 2, the original formula is what we need:

#C = n/V = 0.09/2 = 0.045# #molL^-1#