[CHM 112] Question on Powerpoint

[Andrew J. Pounds]

On 07/22/2015 08:57 PM,  wrote:
>
> Hi Dr. Pounds,
>
>
> I just had a question about one of the example problems on the 
> powerpoint for chapter 17. On slide 12, 100 mL of 1.00M of HCL was 
> added to the solution made in the previous slide. It says that the H+ 
> will combine with the acetate ion and form acetic acid. Does this mean 
> that it is a reverse reaction? If so, why does the ICE table signify 
> that it is a forward reaction (since it is positive on the products 
> side)?
>
>
> Thank you,
>
>

There are two separate things happening here.

First, when you add the strong acid it immediately dissociates and, if 
there is conjugate base available, forms the weak acid.   This has 
nothing to do with the ICE table.

The second thing that happens is that the system then establishes 
equilibrium based on these new initial concentrations.  The $K_a$ value 
is a dissociation constant, and as such we write ICE table for the 
dissociation of the weak acid to form the hydronium ion and the 
conjugate base of the weak acid.

HA + H$_2$O -> H$_3$O$^+$ + A$^-$



-- 
Andrew J. Pounds, Ph.D.  (pounds_aj at mercer.edu)
Professor of Chemistry and Computer Science
Mercer University,  Macon, GA 31207   (478) 301-5627
http://faculty.mercer.edu/pounds_aj

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://theochem.mercer.edu/pipermail/chm112/attachments/20150722/47f974ac/attachment.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: tblatex-11.png
Type: image/png
Size: 709 bytes
Desc: not available
URL: <http://theochem.mercer.edu/pipermail/chm112/attachments/20150722/47f974ac/attachment.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: tblatex-15.png
Type: image/png
Size: 503 bytes
Desc: not available
URL: <http://theochem.mercer.edu/pipermail/chm112/attachments/20150722/47f974ac/attachment-0001.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: tblatex-14.png
Type: image/png
Size: 498 bytes
Desc: not available
URL: <http://theochem.mercer.edu/pipermail/chm112/attachments/20150722/47f974ac/attachment-0002.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: tblatex-13.png
Type: image/png
Size: 419 bytes
Desc: not available
URL: <http://theochem.mercer.edu/pipermail/chm112/attachments/20150722/47f974ac/attachment-0003.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: tblatex-12.png
Type: image/png
Size: 386 bytes
Desc: not available
URL: <http://theochem.mercer.edu/pipermail/chm112/attachments/20150722/47f974ac/attachment-0004.png>