Here is the Kaplan Question...

http://img105.imageshack.us/img105/8494/elevationet3.th.gif (http://img105.imageshack.us/my.php?image=elevationet3.gif)

I thought you had to take into account the Van't Hoff Factor.. shouldn't it be 3 for Na2SO4.. and then the answer should be ~ 100.75

Here is the Kaplan Question...

http://img105.imageshack.us/img105/8494/elevationet3.th.gif (http://img105.imageshack.us/my.php?image=elevationet3.gif)

I thought you had to take into account the Van't Hoff Factor.. shouldn't it be 3 for Na2SO4.. and then the answer should be ~ 100.75

Looks like a mistake to me unless there is something that we are both missing. The only time the Van't Hoff factor would not be included was if the solute was non-ionic and doesn't dissociate (i=1, like C6H12O6). If I'm not mistaken, Na2SO4 is ionic and would dissociate into 3 ions like you said.

Thanks I-Baby. I assumed it was a mistake and I have the same understanding as you about van't hoff factor not mattering for something like glucose. I just wanted to run it by a fellow SDN'er to make sure I wasn't missing something obvious. Thanks again.

Here is the Kaplan Question...

http://img105.imageshack.us/img105/8494/elevationet3.th.gif (http://img105.imageshack.us/my.php?image=elevationet3.gif)

I thought you had to take into account the Van't Hoff Factor.. shouldn't it be 3 for Na2SO4.. and then the answer should be ~ 100.75


yeah you have to consider the 3.
so the answer should be 100.768C

Thanks I-Baby. I assumed it was a mistake and I have the same understanding as you about van't hoff factor not mattering for something like glucose. I just wanted to run it by a fellow SDN'er to make sure I wasn't missing something obvious. Thanks again.

No problem. Actually, seeing that reinforced the concept for me so I should say thank you. GL with your studying!

what is the Vont Hoff Factor?

Thanks.