lboogy Posted March 29, 2007 Share Posted March 29, 2007 Hi everyone, Can I just check with you, is 0.1M 10%? So to get from molar to % we just multiply by 100? Is that correct? thanks in advance...and sorry forthe simplicity Link to comment Share on other sites More sharing options...
ecoli Posted March 29, 2007 Share Posted March 29, 2007 So a 20M solution would be 200 %? Think again. Link to comment Share on other sites More sharing options...
lboogy Posted March 29, 2007 Author Share Posted March 29, 2007 yeah...but i though 1.0 would be the maximum i.e. 100%. could anyone help me please? p.s. if 0.1M was 10%, then 20M would be 2000% not 200% ;-) Link to comment Share on other sites More sharing options...
John Cuthber Posted March 29, 2007 Share Posted March 29, 2007 To understand molarity you need to know what a mole is (and I don't mean a small burrowing mammal). This might help http://en.wikipedia.org/wiki/Molarity#Molarity Link to comment Share on other sites More sharing options...
lboogy Posted March 29, 2007 Author Share Posted March 29, 2007 From wikipedia: "The mole fraction Χ, (also called molar fraction) denotes the number of moles of solute as a proportion of the total number of moles in a solution. For instance: 1 mole of solute dissolved in 9 moles of solvent has a mole fraction of 1/10 or 0.1" I don't understand how this isn't 10%. I know I'm getting wrong, as you guys have told me, but my understanding from this is that the molar of a solution is a percentage the solute takes up of the whole solution. Please tell me what I'm getting wrong! thanks Link to comment Share on other sites More sharing options...
Bignose Posted March 30, 2007 Share Posted March 30, 2007 Please don't take this as in a snarky or mean or putting you down tone. It is not what I mean. But, lboogy, did you read the wili link John posted? Specifically, "Molarity (M) denotes the number of moles of a given substance per liter of solution." Nothing about mole fraction, which is a very different quantity. Molarity has units of moles/liter. Mole fraction would be moles/moles or unitless. Link to comment Share on other sites More sharing options...
ecoli Posted March 30, 2007 Share Posted March 30, 2007 p.s. if 0.1M was 10%, then 20M would be 2000% not 200% ;-) haha.. oh yeah. No, you can definately have more than a 1M solution. Read the provided link. Link to comment Share on other sites More sharing options...
lboogy Posted March 30, 2007 Author Share Posted March 30, 2007 Yeah, so I think I get it now, One mole of a substance contains 6.02 x (10)23 formula units. thanks for your help guys.....I realise my questions must seem a bit daft, sorry. Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now