Consider the titration of 50.0 mL of 0.010 M HA (Ka = 1.0 x 10^-4) with 0.010 M NaOH. (a) Sketch the pH titration curve, and label the equivalence point. (b) How many milliliters of 0.010 M NaOH are required to reach the equivalence point? (c) Is the pH at the equivalence point greater than, equal to, or less than 7? (d) What is the pH exactly halfway to the equivalence point?

Verified step by step guidance

1. Step 1: Determine the initial moles of HA in the solution by using the formula: moles = concentration (M) * volume (L). For HA, this would be 0.010 M * 0.050 L.
2. Step 2: Calculate the volume of NaOH needed to reach the equivalence point. At the equivalence point, the moles of NaOH added will equal the initial moles of HA. Use the formula: volume (L) = moles / concentration (M) of NaOH.
3. Step 3: Analyze the pH at the equivalence point. Since HA is a weak acid and NaOH is a strong base, the solution at the equivalence point will contain the conjugate base A-. The pH will be greater than 7 due to the basic nature of the conjugate base.
4. Step 4: Calculate the pH halfway to the equivalence point. At this point, the concentration of HA equals the concentration of A-, and the pH is equal to the pKa of HA. Use the formula: pH = -log(Ka) to find the pH.
5. Step 5: Sketch the titration curve. Start with the initial pH of the weak acid, show the gradual increase in pH as NaOH is added, mark the equivalence point where the pH rises sharply, and indicate the pH at the equivalence point and halfway to the equivalence point.