chem lec part 3

which a carefully

determined mass of a primary standard is dissolved in a suitable solvent and diluted

to a known volume in a volumetric flask.

A titrant that is standardized sometimes the concentration of a secondary-standard solution is subject to a larger uncertainty than is the concentration of a primary-standard solution.

 the mass of the reagent is measured instead of its volume.

-the “reagent” is a constant direct electrical current of known magnitude that consumes the analyte

the quantity of charge required to

complete a reaction with the analyte

is the measured quantity.

based on determining the quantity of a reagent of known concentration that is required to react completely with

the analyte

 a reagent of known concentration that is used to carry out a volumetric titration.

 a highly purified compound that serves as a reference material in titrations and in other analytical methods.

 a compound whose purity has been

determined by chemical analysis.

Serves as the working standard material

for titrations and for many other

analyses

 the number of equivalents of reagent in the same volume.

The most common way to express concentration for mass titrations 

in which the p-function of analyte (or sometimes the titrant) is plotted as a function of titrant volume

measurements are made on both sides of, but well away from, the equivalence point. Measurements near equivalence are avoided

 In this type of curve, the vertical axis represents an instrument reading that is directly proportional to the concentration of the analyte or

the titrant.

are plots of a concentration-related variable versus titrant volume