12.6.1 Interpretation of Titration Curves

    Cards (69)

    • Acid-base titrations involve the reaction of an acid with a base to determine the concentration
    • A strong acid-strong base titration, such as HCl with NaOH, results in an equivalence point pH of 7.
    • What is an example of a weak acid used in a titration with a strong base?
      CH3COOH
    • Match the titration type with its equivalence point pH:
      Strong acid-strong base ↔️ 7
      Weak acid-strong base ↔️ > 7
    • The equivalence point pH for a strong acid-strong base titration is always exactly 7.
    • The equivalence point in a titration is where the amount of acid equals the amount of base
    • Steps to plot a titration curve
      1️⃣ Prepare the axes
      2️⃣ Plot data points
      3️⃣ Connect the points
    • A buffer region is observed in strong acid-strong base titrations.
      False
    • Match the titration type with its key features:
      Strong acid-strong base ↔️ Sharp rise around pH 7
      Weak acid-strong base ↔️ Gradual pH increase with buffer
    • The equivalence point in a titration curve is indicated by a steep change in pH
    • The equivalence point in a titration curve is always at pH 7.
      False
    • What is the equivalence point in a titration curve?
      Moles of acid = base
    • In weak acid/base titrations, the buffer region is characterized by a gradual change in pH
    • The equivalence point pH for a strong acid-strong base titration is always 7.
    • What is the equivalence point pH for a weak acid-strong base titration?
      77
    • The equivalence point in a titration curve is indicated by a sharp change in pH
    • What is the relationship between pH and pKa at the half-equivalence point for weak acids?
      pH=pH =pKa pK_{a}
    • On what does the pH at the equivalence point depend?
      Type of acid-base titration
    • The equivalence point pH for a strong acid-weak base titration is less than 7.
    • What is the equivalence point pH for a weak acid-weak base titration?
      Near 7 but can vary
    • In weak acid-strong base titrations, the conjugate base reacts with water to produce OH
    • Steps to plot a titration curve:
      1️⃣ Prepare the axes
      2️⃣ Record data points
      3️⃣ Connect the points
    • The equivalence point in a titration curve is always at pH 7.
      False
    • Match the titration type with its equivalence point pH:
      Strong acid-strong base ↔️ 7
      Weak acid-strong base ↔️ > 7
      Strong acid-weak base ↔️ < 7
      Weak acid-weak base ↔️ Near 7 but can vary
    • What happens at the equivalence point in an acid-base titration?
      Reaction between acid and base is complete
    • Strong acid-strong base titrations result in a neutral solution at the equivalence point.
    • Weak acid-strong base titrations lead to a basic solution due to the conjugate base
    • Why does a strong acid-weak base titration result in an acidic solution at the equivalence point?
      Conjugate acid reacts with water
    • Weak acid-weak base titrations always have a pH of 7 at the equivalence point.
      False
    • Match the titration type with its equivalence point pH:
      Strong acid-strong base ↔️ 7
      Weak acid-strong base ↔️ > 7
      Strong acid-weak base ↔️ < 7
      Weak acid-weak base ↔️ Near 7 but can vary
    • A buffering region in a titration curve refers to a pH range where small additions of acid or base cause minimal changes in pH
    • Arrange the key features of a buffering region in a titration curve:
      1️⃣ Presence in weak acid-weak base titrations
      2️⃣ Containment of both the weak acid and its conjugate base
      3️⃣ Stabilization of pH against small changes
      4️⃣ Location slightly before the steep rise near the equivalence point
    • What equation is used to calculate the pH in the buffering region of a titration curve?
      Henderson-Hasselbalch equation
    • The Henderson-Hasselbalch equation is expressed as pH=pH =pKa+ pK_{a} +log[A][HA] \log \frac{[A^ - ]}{[HA]}, where pKapK_{a} is the negative logarithm of the acid dissociation constant
    • Buffering regions are typically found in strong acid-strong base titrations.
      False
    • Why do titration curves for strong acids/bases differ significantly from those for weak acids/bases?
      Ionization properties
    • Match the titration type with its key features:
      Strong acid-strong base ↔️ Sharp vertical rise
      Weak acid-strong base ↔️ Gradual rise, buffer region
    • Strong acids and bases ionize completely in solution.
    • Weak acids and bases partially ionize, creating buffer regions and equivalence points that are slightly acidic or basic
    • What does the acid dissociation constant (KaK_{a}) indicate about an acid?

      Strength of the acid