Imagine that you are titrating 30.00 mL of 0.100 M KOH with 0.100 M HBr (HBr is in the buret). Calculate the pH of the solution after 30.00 mL of acid is added to the base.
Not sure how to do this problem, my standard method is definately not working since you can't take log(0). Any ideas on what I can do?
2006-11-18 10:41:24 · 3 answers · asked by jnieves01 1 in Science & Mathematics ➔ Chemistry
Yea...but how do you do calculate that??
2006-11-18 10:49:27 · update #1
I thought in order to use the ICE method you need the Ka, or pKa, which is not given.
2006-11-18 11:08:07 · update #2
KOH is a strong base and HBr is a strong acid.
greq acid= N*V=a*M*V. HBr is monoprotic so a=1 and
greq acid=1* 0.1*30*10^-3=3*10^-3
greq base= a*M*V. KOH is monovalent base so a=1 and
greq base= 1*0.1*30*10^-3=3*10^-3
You have greq acid= greq base which means you reached the equivalence point. Since both the acid and base are strong the final pH is 7 (there is no hydolysis of the salt) -remember the H+ and OH- coming from the base and acid have completely reacted but [H+] is never 0 since you have the equilibrium for the self dissociation of water.
You could have come to the same conclusion with moles (1:1, stoichiometry, same number of moles thus neither the acid nor the base is in excess, and there is no salt hydrolysis since both are strong electrolytes) but equivalents is the best way to solve titration problems.
2006-11-18 11:37:38 · answer #1 · answered by bellerophon 6 · 0⤊ 0⤋
Relax. The PH is not enough to panic about. If there were no other strange indications, such as glucose, blood, nitrite, etc. on the stick, this is not a too high PH. However, high PH may cause crystals and can create kidney stones and bladder stones, which is not good to have. definitely she must look into it. She must go to a doctor and have a sonogram and have a complete urine analysis at a lab, where they can check on the microscope and they can perform a culture for bacteria. and check for blood, salts, crystals, and so on. Also, the doctors will tell her if she needs some medication or change of diet to adjust her PH. By the way, 5 is too low for PH too, it could create stones at the opposite end. 6-7 is OK.
2016-05-22 01:39:09 · answer #2 · answered by Anonymous · 0⤊ 0⤋
I am struggling to remember my analytical chemistry, but I think you should try the the ICE or IDE method
I = Initial [ ]
C = Change in [ ] (or D for Delta, which the symbol indicating change)
E = End [ ]
I know that also you need to factor in the beginning volume and the final volume. Sorry, I have actively forgotten all my chem!)
2006-11-18 10:51:48 · answer #3 · answered by Silly me 4 · 0⤊ 1⤋