Page 26 - Pharmaceutical Analytical Chemistry III

Random Errors in Chemical Analysis

The Nature of Random Errors

There are always a large number of small, random errors
in making any measurement.

Distribution of Errors (Statistics of repeated Measurements):

Indeterminate errors follow random distribution.

These errors cause data to be scattered more or less
symmetrically around a mean value ( cause the individual

results to fall on both sides of the average value).

Thus, if a graph is constructed by plotting the value of
experimental observation on the x-axis versus the

number of times each value is observed (frequency) on the y-axis,

a normal distribution curve is obtained.