# Homework Help: Dilution Chemistry Problems i dont get it >.<

1. Nov 30, 2007

### king atlantis

ok, our teacher showed us a ton of stuff today, includeing molarity and dilution. i understand molarity but not dilution...any help please?

1. The problem statement, all variables and given/known data
the problems are all like this:
*0.005 L of 1.0 M Hcl is diluted w/ water to 0.125 L
*100.0 ML of 2.0 M HCL is diluted with water to 200 mL.
etc...

3. The attempt at a solution
now, the formula given is M1V1=M2V2

so i would:
0.005L*0.125L=10L*20L
?
for some reason that looks wrong, but like i said, i just dont get it...the teach was a sub, and made it all confusing-like <.<

any help would be appreciated...

2. Nov 30, 2007

### rocomath

well you interpreted all the variables incorrectly

$$M_{1}=\mbox{Molairty}_{\mbox{initial}}$$

$$M_{2}=\mbox{Molarity}_{\mbox{final after dilution}}$$

$$V_{1}=\mbox{Volume}_{\mbox{initial}}$$

$$V_{2}=\mbox{Volume}_{\mbox{final after dilution}}$$

$$M_{1}=\mbox{1.0 M HCL}$$
$$V_{1}=0.005L$$

$$V_{2}=0.125L$$

and so, all you need to do is solve for final Volume

$$M_{1} \times V_{1} = M_{2} \times V_{2}$$

*also, always pay attention to your final units

Last edited: Nov 30, 2007
3. Nov 30, 2007

### MichaelXY

It looks to me like your trying to use Boyles Law P1V1=P2V2, I dont think that applies to your problem. Other thing I noticed is the you converted 100ML to 10L, it should be .1L

Also it seems as though part of the question is missing.

4. Nov 30, 2007

### rocomath

Boyle's Law has nothing to do with this problem. He is simply looking for the final Molarity after dilution.

Last edited: Nov 30, 2007
5. Nov 30, 2007