systematic error

Examples of systematic error in the following topics:

• Accuracy, Precision, and Error

  • Errors can be classified as human error or technical error.
  • Technical error can be broken down into two categories: random error and systematic error.
  • Random error, as the name implies, occur periodically, with no recognizable pattern.
  • Systematic error occurs when there is a problem with the instrument.
  • With multiple measurements (replicates), we can judge the precision of the results, and then apply simple statistics to estimate how close the mean value would be to the true value if there was no systematic error in the system.

• Naming Familiar Inorganic Compounds

  • Now imagine using its systematic name in the same context: "Please pass the α-D-glucopyranosyl-(1,2)-β-D-fructofuranoside!"
  • And the only place you would come across a systematic name such as the rather unwieldy one mentioned above would be in scientific documentation in reference to a sugar that has no simple common name.
  • While its systematic name, "nitrogen trihydride" (which is rarely used), tells you its formula, what it will not tell you is the interesting history of its discovery.
  • But, it is still common practice to refer to the specific substance CH3CH2OH as "alcohol" rather than by its systematic name, ethanol.

• Naming Organic Compounds

  • The increasingly large number of organic compounds identified with each passing day, together with the fact that many of these compounds are isomers of other compounds, requires that a systematic nomenclature system be developed.
  • Such common names often have their origin in the history of the science and the natural sources of specific compounds, but the relationship of these names to each other is arbitrary, and no rational or systematic principles underly their assignments.

• Nomenclature

  • Devising a systematic nomenclature system for heterocyclic compounds presented a formidable challenge, which has not been uniformly concluded.
  • Some monocyclic compounds of this kind are shown in the following chart, with the common (trivial) name in bold and a systematic name based on the Hantzsch-Widman system given beneath it in blue.
  • The Hantzsch-Widman system provides a more systematic method of naming heterocyclic compounds that is not dependent on prior carbocyclic names.
  • Despite the general systematic structure of the Hantzsch-Widman system, several exceptions and modifications have been incorporated to accommodate conflicts with prior usage.
  • As before, common names are in black and systematic names in blue.

• Standard Reduction Potentials

  • Standard reduction potentials provide a systematic measurement for different molecules' tendency to be reduced.

• Naming Molecular Compounds

  • Molecular compounds are named using a systematic approach of prefixes to indicate the number of each element present in the compound.

• Nomenclature of Carboxylic Acids

  • The characteristic IUPAC suffix for a carboxyl group is "oic acid", and care must be taken not to confuse this systematic nomenclature with the similar common system.
  • Some common names, the amino acid threonine for example, do not have any systematic origin and must simply be memorized.

• Prostaglandins

  • The prostaglandins are given systematic names that reflect their structure.

• Naming Hydrates

  • Generate the chemical formula and systematic name of a given inorganic hydrate

• Development of the Periodic Table

  • Although their efforts were in vain, their investigation has ultimately led to a systematic understanding of the chemical world.
  • These observations strengthened the atomic theory and demanded a systematic method of organizing the elements.
  • Scientists began to notice similarities and patterns among known elements, and a great research interest of the 19th century was to develop a systematic method to report and classify them.