Question #b50ac

1 Answer
Jul 10, 2017

Answer:

You can add #900# #"mL"# of distilled water.

Explanation:

We're asked to find out how to dilute a #100#-#"mL"# #0.1M# #"HCl"# solution to a concentration of #0.01M#.

We can dilute solutions like this by adding a certain amount of distilled water until it reaches the desired concentration. We therefore need to find out what the final volume of the solution must be to have a concentrationof #0.01M#.

We can use the dilution equation

#M_1V_1 = M_2V_2#

where

  • #M_1# and #M_2# are the molarities of the concentrated and dilute solutions, respectively

  • #V_1# and #V_2# are the volumes of the concentrated and dilute solutions, respectively

We know:

#M_1 = 0.1M#

#V_1 = 100# #"mL"#

#M_2 = 0.01M#

Plugging these in and solving for #V_2#:

#V_2 = (M_1V_1)/(M_2) = ((0.1cancel(M))(100color(white)(l)"mL"))/(0.01cancel(M)) = 10^3# #"mL"#

Now that we know the necessary plume to attain a concentration of #0.01M#, we subtract the original volume from this to find out how much distilled water must be added:

#10^3# #"mL"# #- 100# #"mL"# #= color(blue)(900# #color(blue)("mL"#