Question

Consider the titration of a 23.0 ml sample of 0.105 moll-1 ch3cooh (ka=1.8×10-5) with 0.130 moll-1 naoh. Determine the initial pH.

Answer 1

The initial pH of a 23.0 ml sample of 0.105 M CH3COOH (Acetic Acid) with a Ka of 1.8×10^-5 can be calculated using the acid ionization constant expression and the Henderson-Hasselbalch equation.

Step-by-step explanation:

The initial pH of a 23.0 ml sample of 0.105 M CH3COOH with a Ka value of 1.8×10-5 is determined using the expression for the ionization of acetic acid and the Henderson-Hasselbalch equation. To find the initial pH before any NaOH is added, we set up the expression for Ka as follows: Ka = [H+][A-]/[HA]. Assuming initial ionization is negligible compared to the concentration of the acid, the concentration of H+ can be estimated using the square root of (Ka × Concentration of the acid). Thus, pH = -log([H+]).