Chemistry Help (note somewhat advanced) OK, well I'm in gen chem 2 in college, but since I placed out of the class, I only have to take the lab. It has been a good year and a half since I have done any inorganic chem, so I'm kinda rusty. I have done the work, now all I am looking for is someone who is somewhat more advanced than myself to tell me if I am thinking along the right lines. If I am not, then I would appreciate a nudge in the right direction. :innocent: k, here are the two questions. 1) We performed a complexometric titration, involving EDTA. The unknown solution contained H+, and so before we titrated the unknown solution with the EDTA (to find out the concentration of other ions in the solution [magnesuim and zinc]), we neutralized the H+ by adding a perdetermined amount of NaOH. Also, the solution was buffered to pH10, so that the Mg and Zn would form the complex more easily. The question is, why was the acid neutralized? Answer: if the acid were not neutralized, then the pH would have been significantly lower, which means that the complex may not have been able to form. 2) The capacity of an ion exchange resin is usually expressed on the basis of the number of 'milliequivalents' of charge that can be exchanged per mL of the resin bed. If a packed column with a capacity of 3.5 milliequivalents/mL of resin has a total resin volume of 15.5mL, what is the maximum number of millimoles of Ca2+ that could be exchanged before the resin is saturated? Answer: (3.5 * 15.5) / 2 = 27.125 millimoles of Ca2+. The (3.5*15.5) gives you the total amount of charge that can be stored, and then you divide by 2, because each millimole of Ca2+ has a charge of 2. Does this sound right? Thanks for your help if you can indeed help. peace :teeth: EDIT: ok, ill just go finish my differential equations homework, read the italian play, and then come back and see whats going on... what i would give for it to be friday, there to be a bottle of captain morgans rum by my side, and a party with hot girls to go to... ahhhhhhhhhhhh.