November 22, 2024, 09:58:31 AM
Forum Rules: Read This Before Posting


Topic: Dilution problems  (Read 5036 times)

0 Members and 1 Guest are viewing this topic.

fbpearce

  • Guest
Dilution problems
« on: August 26, 2006, 04:57:53 PM »
It has been quite some time since gen chem for me, and I'm having some trouble refreshing myself on how to do dilutions properly. Here's my problem

I have .182g of a substance that has a mw of 364g/mol. I first want to put it into 1L of distilled water. So working w/ moles of my substance I would come up with

.0005 moles/ L

After figuring out the amount of moles for a 10 mL aliquot I need to dilute it w/ 90mL of distilled water. Would I use the m1v1/m2v2 equation?

Thanks!

Ben


Offline sdekivit

  • Chemist
  • Full Member
  • *
  • Posts: 403
  • Mole Snacks: +32/-3
  • Gender: Male
  • B.Sc Biomedical Sciences, Utrecht University
Re: Dilution problems
« Reply #1 on: August 26, 2006, 05:27:10 PM »
I have .182g of a substance that has a mw of 364g/mol. I first want to put it into 1L of distilled water. So working w/ moles of my substance I would come up with

.0005 moles/ L

Ben

There are 3 ways:

(1)The first one you already mentioned: c1*V1 = c2*V2.

(2)Calculate the dilution factor. We dilute here from 10 mL to 100 mL so we dilute 10 x --> concentration decreases 10x.

(3)Calculate the amount of mol in 10 mL solution and divide that by 100 mL to gain the new concentration.

Actually (1) and (3) are the same.

Sponsored Links