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Compare strong acid-strong base and weak acid-strong base titrations.
Strong Acid-Strong Base: Equivalence point pH is 7, no buffer region. Weak Acid-Strong Base: Equivalence point pH is >7, has a buffer region before the equivalence point.
Compare the pH at the equivalence point for titrations involving weak acids/strong bases versus strong acids/strong bases.
Weak acid/strong base: pH > 7 at equivalence point. Strong acid/strong base: pH = 7 at equivalence point.
What is the difference between the equivalence point and the half-equivalence point in a titration?
Equivalence point: Moles of titrant = moles of analyte. Half-equivalence point: Half the volume to reach the equivalence point; pH = pKa (or pOH = pKb) for weak acids/bases.
Compare titrating a weak acid with a strong base versus titrating a weak base with a strong acid.
Weak acid with strong base: pH at equivalence point is basic. Weak base with strong acid: pH at equivalence point is acidic.
Compare the shapes of titration curves for strong acid-strong base titrations versus weak acid-strong base titrations.
Strong acid-strong base: Sharp, abrupt change in pH near the equivalence point. Weak acid-strong base: More gradual change in pH, buffer region present, less sharp change at the equivalence point.
Define 'analyte' in titration.
The solution with the unknown concentration in a titration.
Define 'titrant' in titration.
The solution with the known concentration that is added to the analyte in a titration.
Define 'equivalence point'.
The point in a titration where the moles of titrant added equals the moles of analyte in the solution.
Define 'titration curve'.
A plot of pH change versus the volume of titrant added during a titration.
Define 'half-equivalence point'.
The point in a weak acid/base titration where half of the acid/base has been neutralized, resulting in pH = pKa or pOH = pKb.
Define 'buffer'.
A solution that resists changes in pH due to the presence of a weak acid and its conjugate base, or a weak base and its conjugate acid.
Describe the steps to find the concentration of HF when titrating with NaOH, given the equivalence point occurs when 20mL of 0.1M NaOH is added to 10mL of HF.
- Use the equation . 2. Plug in the known values: . 3. Solve for : .
What are the steps to determine the pH of a solution formed from titrating a weak acid with a strong base?
- Write the balanced reaction equation. 2. Determine the initial moles of weak acid and strong base. 3. Perform stoichiometry to find the remaining moles of weak acid and conjugate base after the reaction. 4. Use the Henderson-Hasselbalch equation to calculate the pH.
Outline the general steps of acid-base titration.
- Prepare the solutions of titrant and analyte. 2. Carefully add titrant to the analyte using a burette. 3. Monitor the pH change using an indicator or pH meter. 4. Stop adding titrant when the equivalence point is reached (indicated by a color change or a sharp pH change). 5. Calculate the unknown concentration using stoichiometry.
Describe the steps to determine the pH of a solution formed from titrating a weak base with a strong acid.
- Write the balanced reaction equation. 2. Determine the initial moles of weak base and strong acid. 3. Perform stoichiometry to find the remaining moles of weak base and conjugate acid after the reaction. 4. Use the Henderson-Hasselbalch equation (for bases) to calculate the pOH. 5. Convert pOH to pH using pH = 14 - pOH.
What are the steps to calculate the pH at the equivalence point of a weak acid-strong base titration?
- Determine the moles of conjugate base formed at the equivalence point. 2. Calculate the concentration of the conjugate base. 3. Set up an ICE table for the hydrolysis of the conjugate base. 4. Calculate the hydroxide ion concentration using the Kb expression. 5. Calculate the pOH and then the pH.