[mds33200]

Hi, although I am not in high school, I just have a simple question. I remember doing this stuff when I was in high school however, so I felt this section would be the best place to post it.

I have 118 mL of a cleaning solution (the concentration is 100%) and I need to dilute it to a 5% solution by adding a solvent (odorless mineral spirits).

I used google to try to find an answer and I found an equation I think I have to use, but I am not sure if I have to convert the concentrations or volumes first or not. Any advice is appreciated!


C1 x V1 = C2 x V2
So would I do:
100 x 118 mL = 5 x ?

[JGK]

% concentrations can be expressed as follows:

g of solute per 100 mL solution (w/v).
mL of solute per 100 mL solution (v/v).
g of solute per 100 g solution (w/w).

for your dilution use v/v

[Borek]

http://www.chembuddy.com/?left=concentration&right=dilution-mixing

[mds33200]

JGK- I saw you said "for your dilution use v/v". I am a bit confused what you mean by that, can you please elaborate a bit on that?

Borek- I went to that website and I dont understand how I would set up the equasion that way, do I have to convert something to moles to use that one?

Sorry people, havent taken a chem class in over a few years so I am more then a bit rusty with this stuff. Any further help would be greatly appreciated!

[squiros]

so you have 118 mL of 100%. if you double the volume, you'd get 50% concentration, right? which would involve 118 mL of filler. as such, to turn 100% into 5%, your dilution needs to be in a ratio of 1:20. so if 118 mL is that 1 part, the other 19 parts of equal volume will be filler. that means 19*118 = 2242 mL.

on the other hand, if you don't want to use all of it, you can think of it another way. take 1 mL of concentrate and 19 mL of dilute, this will give you 20 mL of 5%. you can scale this up for as much or as little as you'll need.

you don't need moles or molar mass. you would need the chemical composition of the cleaning agent to get moles.

[mds33200]

Squiros- thanks, makes sense when I think of it that way. Have a good one and thanks again for your *delete me*

To the other posters- I wasnt quite clear on what you meant, but thanks for replying!

-Mark S.