NEUTRALIZATION

• What is the purpose of neutralization titrations?

  To determine acidity or basicity of compounds
• In what fields are neutralization titrations used?

  In virtually all fields of chemistry
• What types of compounds can be determined using neutralization titrations?

  Inorganic or organic compounds
• What are the common titrants used in neutralization titrations?

  Strong acids or bases
• What is the most common base titrant?

  NaOH
• Why is NaOH not considered a primary standard?

  It contains water and impurities
• How must NaOH be treated before use in titrations?

  It must be standardized after removal of carbonate
• What are some strong acids used as titrants?

  HNO3, H2SO4, HClO4
• Why is HCl commonly used over other strong acids?

  It is less hazardous and easier to handle
• What is a primary standard material for base titrants?


  Potassium acid phthalate
• What is the molecular weight of potassium acid phthalate?

  204.2
• What are the advantages of potassium acid phthalate as a primary standard?

  High purity and thermal stability
• What is the pKa of 2-furonic acid?

  3.06
• What is a disadvantage of using benzoic acid as a primary standard?

  It is not very soluble in water
• What is the pKa of sulfamic acid?

  0.987
• What is the role of sodium carbonate in titrations?

  It is a common primary standard
• What is the molecular weight of sodium tetraborate?

  190.69
• What is the main disadvantage of sodium tetraborate?

  Presence of hydrate water
• What is the molecular weight of 4-aminopyridine?

  Low molecular weight
• What are acid-base indicators?

  Weak organic acids or bases with color changes
• Why must the amount of indicator be small?

  To avoid consuming titrant significantly
• What is the ionization equilibrium for an acid-type indicator?

  HIn + H2O ⇌ H3O+ + In-
• What does the equilibrium constant expression for an acid-type indicator represent?

  Ka = [H3O+][In-]/[HIn]
• What does a pH range of pKa ± 1 indicate?

  Indicator color changes are predominant
• What is the most suitable indicator for a titration?

  One with pKa closest to equivalence point
• What is a determinate error in titration?


  When indicator color change differs from equivalence
• What is an indeterminate error in titration?


  Limited ability to distinguish indicator colors
• What does a titration curve plot?

  pH versus volume of titrant added
• What are the stages of titration?

  Before, pre-equivalence, equivalence, post-equivalence
• What happens at the equivalence point in a strong acid-strong base titration?

  Only salt and water remain
• How does concentration affect the titration curve?

  Higher concentration leads to larger pH changes
• What is the reaction for acetic acid titrated with sodium hydroxide?


  CH3COOH + OH- → CH3COO- + H2O
• What is the role of NH3 in titration with HCl?


  It acts as a weak base
• How does the concentration and ionization constant affect the titration curve?

  They shape the curve for weak acids and bases
• What is the Kjeldahl method used for?


  Nitrogen analysis in samples
• What happens to nitrogen in the Kjeldahl method?

  It converts to ammonium ion
• How is sulfur analyzed using neutralization titration?

  By burning and collecting SO2/SO3
• What are some organic functional groups determined by neutralization titration?

  Carboxylic, amine, ester, hydroxyl, carbonyl
• What is the purpose of double indicator titration?

  To analyze carbonate and phosphate mixtures
• What is the role of phenolphthalein in titration?

  It indicates the alkaline endpoint