Sarahisme Posted June 13, 2005 Share Posted June 13, 2005 hey could i have some help on how to do this question? Thanks Sarah Link to comment Share on other sites More sharing options...
BenSon Posted June 13, 2005 Share Posted June 13, 2005 Thats a bit hard to do without acidity constants eh? Do they give you those? Edit: Now that i think about it if you can't calculate I think it's experiment 3 because for that to be true it would have had to dissociate 100% and i don't think anything dissocitates perfectly. ~Scott Link to comment Share on other sites More sharing options...
Sarahisme Posted June 13, 2005 Author Share Posted June 13, 2005 the answer given is (d) but yeah i've got no idea how to do it really :S Link to comment Share on other sites More sharing options...
scientistsahai Posted June 13, 2005 Share Posted June 13, 2005 Thats a bit hard to do without acidity constants eh? Do they give you those? Edit: Now that i think about it if you can't calculate I think it's experiment 3 because for that to be true it would have had to dissociate 100% and i don't think anything dissocitates perfectly. ~Scott The answer in most probability shud b the 4th one. Since H2SO4 dissociates in 2 steps as: H(+) + HSO4(-) AND H(+) + SO4(2-) Hence the complete dissociation of H2SO4 does not occur due to common ion effect(H here). Hence the ionsization will be incomplete and hence higher pH(less acidic) Link to comment Share on other sites More sharing options...
BenSon Posted June 13, 2005 Share Posted June 13, 2005 Get out, thats diprotic and seeing as you aren't given acidic constants you would have to assume that theoreticly the second dissociation could be 99%?? Or do you mean that the pH would be >2? ~Scott Link to comment Share on other sites More sharing options...
scientistsahai Posted June 13, 2005 Share Posted June 13, 2005 No, the acid is definitely diprotic but there is 2nd dissociation which is hindered by the strong 1st dissociation of H2SO4[due to common ion effect H(+)] Hence the higher pH. BenSon the higher pH means high value and weaker acid thus the actual pH shud theoretically lie between 1.99 and 2.2 under STP and in water. Link to comment Share on other sites More sharing options...
Bluenoise Posted June 13, 2005 Share Posted June 13, 2005 Sarahisme, there is a seperate forum for this. Could you please start posting these in the homework help form. You're really clogging this one up. Link to comment Share on other sites More sharing options...
EwenM Posted June 13, 2005 Share Posted June 13, 2005 It doesn't matter how dissociated the H2SO4 is, the maximum [H+] it can give is 0.02 M, which corresponds to a pH of 1.7. To reach pH 1.4, [H+] must be 0.04 M - impossible with 0.01 M H2SO4 Link to comment Share on other sites More sharing options...
BenSon Posted June 13, 2005 Share Posted June 13, 2005 Thankyou Ewen Makes sense ~Scott Link to comment Share on other sites More sharing options...
Sarahisme Posted June 13, 2005 Author Share Posted June 13, 2005 Sarahisme' date=' there is a seperate forum for this. Could you please start posting these in the homework help form. You're really clogging this one up.[/quote'] ok sorry Link to comment Share on other sites More sharing options...
BenSon Posted June 14, 2005 Share Posted June 14, 2005 Hey sarah, seeing as your a regular why don't you start one thread in the chemistry forums that you post all your questions in? It will save some room and probably be more responsive then the homework help section. Just a thought. ~Scott 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