Chapter 6 - Chapter 6 Random Error The Nature of Random...

Info iconThis preview shows pages 1–12. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Chapter 6 Random Error The Nature of Random Errors Random, or indeterminate, errors occur whenever a measurement is made. This type of error is caused by the many uncontrollable variables that are an inevitable part of every physical or chemical measurement. There are many contributors to random error, but often we cannot positively identify or measure them because they are small enough to avoid individual detection. The accumulated effect of the individual random uncertainties, however, causes the data from a set of replicate measurements to fluctuate randomly around the mean of the set. Three dimensional plot showing absolute error Frequency distribution Range of measured values, mL Sources of Random Errors Sources of random uncertainties in the calibration of a pipet include (1) visual judgments, such as the level of the water with respect to the marking on the pipet and the mercury level in the thermometer; (2) variations in the drainage time and in the angle of the pipet as it drains; (3) temperature fluctuations, which affect the volume of the pipet, the viscosity of the liquid, and the performance of the balance; and (4) vibrations and drafts that cause small variations in the balance readings. Undoubtedly, numerous other sources of random uncertainty also operate in this calibration process. It is difficult or impossible to determine the influence of any one of the random errors arising Results of coin flipping Normal error curves Samples and Populations A finite number of experimental observations is called a sample of data. The sample is treated as a tiny fraction of an infinite number of observations that could in principle be made given infinite time....
View Full Document

Page1 / 24

Chapter 6 - Chapter 6 Random Error The Nature of Random...

This preview shows document pages 1 - 12. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online