Now, we are titrating weak acid with strong base. For example in this condition we use 50 mL of 0.1M CH3COOH as weak acid and 0.1M NaOH as strong base. Firstly, we must calculate NaOH required to reach the equivalent point. (see eq. 1)
On the condition where there aren’t NaOH , we must calculate the pH of the solution. Acetic acid is weak acid, so the reaction in solution is (see eq. 2)
So, from the result above, pH solution is 2.88. Then, NaOH beginning added to the solution, this makes some acetic acid converted to buffer or conjugate base. In this condition we must use special formula to calculate its pH, the formula used in this condition is Henderson-Hasselbalch equation, (see eq. 3)
From the reaction, there is unreacted acetic acid which causes from higher of constant for reaction. So, before equivalent point the concentration of acetic also must be calculated using equation , (see eq. 4-5)
Acetic acid dominate at the equivalent point than NaOH added, although the concentration of two reagent are similar. This is because the reaction is effectively proceeds to completion. Acetic ion is weak base, so it must be calculated using equation (see eq. 6-7)
After equivalent point reached, NaOH is excess in the solution. This condition calculated using normal equation such as titrating strong acid with weak base. The equation is (see eq. 8)
On the condition where there aren’t NaOH , we must calculate the pH of the solution. Acetic acid is weak acid, so the reaction in solution is (see eq. 2)
So, from the result above, pH solution is 2.88. Then, NaOH beginning added to the solution, this makes some acetic acid converted to buffer or conjugate base. In this condition we must use special formula to calculate its pH, the formula used in this condition is Henderson-Hasselbalch equation, (see eq. 3)
From the reaction, there is unreacted acetic acid which causes from higher of constant for reaction. So, before equivalent point the concentration of acetic also must be calculated using equation , (see eq. 4-5)
Acetic acid dominate at the equivalent point than NaOH added, although the concentration of two reagent are similar. This is because the reaction is effectively proceeds to completion. Acetic ion is weak base, so it must be calculated using equation (see eq. 6-7)
After equivalent point reached, NaOH is excess in the solution. This condition calculated using normal equation such as titrating strong acid with weak base. The equation is (see eq. 8)
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