For all u chem whizzes....

Test Preparation
1

<p>explain to me if this is techinically correct:
<a href="http://apcentral.collegeboard.com/repository/sg_chemistry_02_11388.pdf%5B/url%5D"&gt;http://apcentral.collegeboard.com/repository/sg_chemistry_02_11388.pdf&lt;/a&gt;&lt;/p>

<p>I am talking about #1d it is on page 4.
according to them i can simply solve for OBr- however this does not make sense because wouldn't the HOBr dissociate giving H+ ions as well ? and how does the addition of OBr- affect the pH anyways?</p>

2

<p>well your making a buffer so you want to find the amount of cojugate base needed to buffer at that specific ph. Remeber at the buffer zone -log(HA/A) = 0 because -log 1 = 0 so its out of the equation and the pka = ph. So yes they are right in solving for OBr-, then you can figure out how much base must be added to create that buffer for that specific ph</p>

3

<p>thanks!
my message is now not too short</p>