volumetric analysis/ acid-base

• Volumetric Analysis


  this is a method that involves the measurement of the volume of a solution of known concentration

  also known as "Standard Solution"
• Titrimetric Analysis

  • The concentration of a solution is determined by causing the solution to react with another solution of known concentration
  • Also known as volumetric analysis
• Normal Solution

  contains gram-equivalent of substance
• Moral solution


  contains 1 mol of the substance
• Volumetric Apparatus (Made to contain)

  • Beaker
  • Erlenmeyer
  • Graduated cylinder
• Volumetric Apparatus (Made to deliver)

  • Burette
  • Pipette
  • Graduated cylinder
• what are the two principles involved?

  • Volumetric Analysis
  • Gravimetric analysis
• Types of Burette

  Mohr Burette - alkalimetry (AKA alkali burette)

  Geissler Burette – acidimetry
• Sources of Error in The Use of Volumetric Apparatus

  • Improper cleaning of the apparatus
  • Parallax Error
  • Variation in Temperature
  • Air bubbles that trap
• Elements of Titration

  • Standard Solution
  • Primary Standard
• Secondary Standard


  this is a compound whose purity has been established by chemical analysis
• Analyte 


  the solution whose concentration has to be determined
• indicator

  this is a substance that changes color of the solution in response to a chemical change.
• Terms Involved in Titration

  • Standardization
  • Equivalent Point
  • Endpoint
  • Titration error
• standardization


  this is a process that is used to determine the concentration of a solution of known concentration by titration
• equivalent point


  this is the point in titration when stoichiometrically different amounts of analyte and titrant react
• end point


  this is now the point in titration where we stop adding the titrant
• Titration error


  the determinate error in titration due to the difference between the endpoint and equivalence point.
• Types of Chemical Reaction

  • Neutralization Titration
  • Complexometric Titration
  • Precipitation Titration
  • REDOX Titration
• Neutralization Titration

  also known as Acid/base titration → aqueous and non-aqueous
• Complexometric Titration


  • Involves metal-ligand complexation.
  • Determine the concentration of metal ions.
• Precipitation Titration


  • Endpoint is the presence of precipitate.
  • (Ex. Argeometric → silver salts)
• REDOX titration

  LEORA, GEROA - transfer of electrons
• LEORA - Less Electron Oxidized Reducing Agent

  GEORA - Gain Electron Reduced Oxidizing Agent
• Reducing agent - is always being oxidized, which is why it is losing electrons.

  oxidizing agent - is being reduced to gain electrons
• Theories in the change of color of INDICATORS

  • Physiochemical Theory
  • Organic Theory
  • Colloidal Theory
• Physiochemical Theory

  change in color will happen when there is an increase or decrease of ion concentration.
• Organic Theory

  change in color will happen when there is change of molecular structure of solution
• Colloidal Theory


  change in color will happen when there is change in size of the colloidal particle
• Automatic Titration


  Involves electrochemical sensing technique.
• Titration Techniques

  • Manual Titration
  • Automatic Titration
• Difficulties in Manual Titration:

  ✓ Reading the meniscus

  ✓ Filling of burette with titrant

  ✓ Reading the volume of the titrant

  ✓ Determination of end point

  ✓ Standardization of titrant

  ✓ Error in computation
• Manual Titration

  ➢ Burette

  ➢ Titrant

  ➢ Analyte

  ➢ Indicator

  ➢ Processor

  ➢ Detector
• Types of Titration

  1. Direct Titration (simplest)
  2. Indirect Titration
  3. Residual/Back Titration
• analyte + reactant → intermediate product

  intermediate product + titrant → endpoint
• Also known as Neutralization Titration

  Acid/Base Titration
• Neutralization Reaction


  A solution of an acid is usually added to a solution of a base until the base is exactly neutralized and neither acid nor base exists
• acid

  Taste sour.

  React with some metals to give off hydrogen gas
• bases

  Taste bitter.

  Feel slippery

  Dissolve fats and oils
• Proteolytic Reaction


  • transfer of proton
  • this is a process whereby a proton is transferred from one molecule to another.