[slu1986]

A 0.18 M NaOH solution is used to titrate the HCl solution resulting when 40 mL of a 0.2 M CaCl2 solution is run through an ion exchange resin.  If 4.67 mmoles of Ca (II) are retained on the column of resin, how many milliliters of the NaOH solution will be required to neutralize the HCl coming off?

I am so confused on how to solve this problem.  Could someone please guide me in the right direction on how to solve this problem? I don't want the answer, just need someone to explain to me where to start in solving the problem.  If someone could do that I would appreciate it thanks.

[Borek]

Can you write reaction equation of the process that take place in the column?

[slu1986]

Can you write reaction equation of the process that take place in the column?

No it's one of my questions in my lab manual.  It doesn't show a reaction. 

[Borek]

But you should know what is happening in the column, don't you? That's the basis of the whole process. At least try to describe it in words.

[slu1986]

But you should know what is happening in the column, don't you? That's the basis of the whole process. At least try to describe it in words.
[/quote/]

Somehow we had an error when we did this experiment and didn't get to finish or obtain data.  The resin in the burette kept getting clogged in the stopcock even though we had a piece of cotton to prevent the resin from seeping in there. The teacher gave us a new stopcock and it did the same thing.  So because of that our mixture didn't contain any of the CaCl2 that we added to the column because it couldn't drip out of the burette. So when we added phenolthalein to the mixture it didn't turn clear b/c it wasn't an acid so there was no point in titrating a mixture to get the endpoint if it wasn't an acid.  So no I don't know what is supposed to be happening in the column, I just know that there is supposed to be an acid in the flask from the CaCl2 and water added to the column in the burette.

[Arkcon]

Somehow we had an error when we did this experiment and didn't get to finish or obtain data.  The resin in the burette kept getting clogged in the stopcock even though we had a piece of cotton to prevent the resin from seeping in there. The teacher gave us a new stopcock and it did the same thing.  So because of that our mixture didn't contain any of the CaCl2 that we added to the column because it couldn't drip out of the burette. So when we added phenolthalein to the mixture it didn't turn clear b/c it wasn't an acid so there was no point in titrating a mixture to get the endpoint if it wasn't an acid.  So no I don't know what is supposed to be happening in the column, I just know that there is supposed to be an acid in the flask from the CaCl2 and water added to the column in the burette.

Let me just start off by quoting you correctly.  Now, leaving aside  your unfortunate procedure error -- these things happen.  Can you rewrite your given lab exam question in the format your textbook would give it, then solve it?

How much NaOH is needed, to neutralize how much HCl, for a given amount of CaCl₂, absorbed by the resin?