Page 73 - Illustrated Pocket Dictionary of Chromatography

ETHERS 69

error associated with its accepted value. In a very simplistic fashion,
the error in the obtained response of the unknown (dependent vari-
able, y) is transferred to the standard curve and the resulting range
of x is determined.

There are two representations of estimated error: Error bars provide an estimate
of the associated error with an individual datum. The error band represents an esti-
mate of the error associated with data along a best-fit curve.

error propagation When more than one measurement occurs
during the course of an analysis, each measurement step will have an
error propagated through to the answer. For example, an assay that
includes weight determination, dilution, injection volume, peak inte-
gration, and concentration determination from a calibration curve will
have at least five independent sources of error that will be reflected
in the overall uncertainty of the final reported value.
error, relative The absolute error divided by the true value, X:

relative error = ( absolute error) X

ethers Ethers have the general functional group R—O—R¢ and can
be symmetric (e.g., CH 3CH 2OCH 2 CH 3, diethyl ether or ethyl ether),
asymmetric [e.g., CH 3 —O—C(CH 3) 3, methyl tert-butylether], or cyclic