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Aisha_18
Mar 8, 2009, 10:25 AM
6. Given a 1.0M solution of acetic acid pKa= 4.76 and sodium acetate, describe how you would prepare a 1.0L of 0.10M acetate buffer.

asking
Mar 8, 2009, 11:03 PM
Hi Aisha,
We can't do homework for you, plus this really belongs in chemistry. I'm going to ask that it be moved to the appropriate board. But you will still have to make some effort to do part of it before anyone is likely to help.



Do not simply retype or paste a question from your book or study material

We won't do your homework questions for you.
You were given the assignment for you to learn.

If you come up with your own answer and post it for us to critique that is within reason.

If you have some SPECIFIC questions that you couldn't find or didn't understand, we may help with that.
But this is your assignment, so show us you have at least attempted to complete it on your own.

Thank you.

Perito
Mar 9, 2009, 07:34 AM
Given a 1.0M solution of acetic acid pKa= 4.76 and sodium acetate, describe how you would prepare a 1.0L of 0.10M acetate buffer.

You want 0.1 moles per liter of acetate. Acetate comes from both acetic acid and from sodium acetate (One mole of acetate per mole of compound in both cases). So, you probably want a 50/50 butter. First, decide how much of the final solution you want. Do you want 1 liter of 1.0 M solution, or do you want 100 mL or another volume. The amounts you add depend on how much you prepare.

Weigh out sodium acetate -- 0.05 moles per liter of final solution. Figure out how much. You know the concentration of acetic acid, so figure out the volume of acetic acid to be added to make 0.05 moles per liter of the final solution. Hint: if you have 1.0 Moles/Liter of solution and you add 1 liter, you'll get 1 mole of acetic acid.

Add the sodium acetate and the acetic acid to a volumetric flask of the appropriate size (whatever you decided on) and add water to fill to the calibration mark.