qualitative analysis

Examples of qualitative analysis in the following topics:

• Solubility Product Principle and Qualitative Analysis

  • Solubility product principle is used in qualitative analysis to determine composition of a compound by separation of ions in a solution.
  • Classical qualitative inorganic analysis is a method of analytical chemistry that seeks to find the elemental composition of inorganic compounds.
  • The entire traditional qualitative-analysis scheme is based on the use of these equilibrium constants to determine the correct precipitating ions and the correct strategy.
  • Precipitation is used in qualitative chemical analysis.
  • Describe the application of the solubility product principle in the qualitative analysis of a solution.

• Chemical Analysis

  • Two common techniques are precipitation analysis and colorimetric analysis.
  • These methods are called classical qualitative inorganic analysis.
  • Classical qualitative inorganic analysis is a method of analytical chemistry that seeks to find the elemental compositions of inorganic compounds.
  • This happens because cationic analysis is based on the solubility products of the ions.
  • Precipitation analysis can be used to determine the chemical makeup of the solution.

• The Collision Theory

  • Collision theory provides a qualitative explanation of chemical reactions and the rates at which they occur, appealing to the principle that molecules must collide to react.
  • Collision Theory provides a qualitative explanation of chemical reactions and the rates at which they occur.
  • This fundamental rule guides any analysis of an ordinary reaction mechanism.

• Regioselectivity and Lewis Acid Catalysis

  • Unfortunately, neither molecular orbital symmetry analysis nor the simple mnemonic rules based on electron counts explain these regioselectivities.
  • A qualitative representation of the relative magnitude of terminal orbital coefficients for the HOMO and LUMO orbitals of alkenes (dienophiles) and dienes substituted in this common manner are in the first diagram below.
  • In many cases, this analysis of HOMO and LUMO orbital coefficients also provides a good explanation for the beneficial influence of Lewis acid catalysis.

• Acyl Group Substitution

  • Different carboxylic acid derivatives have very different reactivities, acyl chlorides and bromides being the most reactive and amides the least reactive, as noted in the following qualitatively ordered list.
  • This analysis also predicts the influence these substituent groups have on the reactivity of carboxylic acid derivatives toward nucleophiles (Z = O in the illustration).

• Combustion Analysis

  • Combustion analysis is commonly used to determine the relative ratios of carbon, hydrogen, and oxygen in organic compounds.
  • Combustion analysis is an elemental analytical technique used on solid and liquid organic compounds.
  • Combustion analysis is commonly used to analyze samples of unknown chemical formula.
  • In combustion analysis, the products, carbon dioxide and water vapor, are trapped by absorption onto reactive solids located in tubes above the reaction vessel.
  • Combustion analysis can also be performed using a CHN analyzer, which uses gas chromatography to analyze the combustion products.

• Isomers

  • Combustion analysis yielded the ratio of carbon to hydrogen by measuring the amount of carbon dioxide and water produced, and a rough molecular weight was obtained from boiling point studies.
  • Although these intensities are roughly proportional to the number of atoms of a given kind, other factors are influential.Consequently, 13C nmr provides a very good qualitative count of different kinds of carbon atoms in a molecule, but a poor quantitative count of each.
  • The first two compounds cannot be distinguished by the number of carbon signals; however, a careful analysis of the chemical shifts permits an assignment to be made.

• Changes in Energy

  • The concept of entropy can be described qualitatively as a measure of energy dispersal at a specific temperature.

• Physical Properties of Covalent Molecules

  • Discuss the qualitative predictions of covalent bond theory on the boiling and melting points, bond length and strength, and conductivity of molecules

• A Structure Formula Relationship

  • This molecular formula analysis may be extended beyond hydrocarbons by a few simple corrections.