How to Calculate Ph at Half Equivalence Point
K_b 556x10-10 OH-HAA- x201-x. We can now substitute these back into the weak. 18 3 Ph Curves Part 2 Hl Youtube K b is not given but we can calculate it easily from ionic product of water K w and K a via the formula K w K aK b. . Therefore we can use the formula of weak base to calculate the OH-concentration at this equivalence point. Thus pKa 340. Similar method for Strong base vs Strong Acid. Weak Acid Strong Base Titration Curve pH is greater than 7 at the equivalence point 10. PH pKa at one half of the equivalence point Kb 18 x 10-5. This is the equivalence point halfway up the steep curve. There are 3 cases. See pH of weak acids and bases lecture and pH cheat sheet for details of calculation. HC 3H 5O 2 0275 mol L 0030 L 000825 mol NaOH 0200 mol L 004125 L 000825 mol I 00825 00825 0 - E 0 0 000825 mol - C 3H 5O 2 000825 mol 007125 L 0116 M H 2O C 3H 5O 2 ä OH HC 3 H 5 O 2 initial 0116 0 0 change x x x ...





