The Laboratory Notebook
The Laboratory Notebook
** A laboratory
notebook is needed to record measurements and observations concerning an
analysis.
** The book
should be permanently bound with consecutively numbered pages (if necessary,
the pages should be hand numbered before any entries are made).
** Most
notebooks have more than ample room, so there is no need to crowd entries. The
first few pages should be saved for a table of contents that is updated as
entries are made.
Maintaining a Laboratory Notebook
(1) Record all
data and observations directly into the notebook in ink. Neatness is desirable,
but you should not achieve neatness by transcribing data from a sheet of paper
to the notebook or from one notebook to another. The risk of misplacing—or
incorrectly transcribing—crucial data and thereby ruining an experiment is
unacceptable.
(2) Supply each
entry or series of entries with a heading or label. A series of weighing data
for a set of empty crucibles, for example, should carry the heading “empty crucible
mass” (or something similar), and the mass of each crucible should be identified
by the same number or letter used to label the crucible.
(3) Date each
page of the notebook as it is used.
(4) Never attempt
to erase or obliterate an incorrect entry. Instead, cross it out with a single horizontal
line and locate the correct entry as nearby as possible. Do not write over
incorrect numbers. With time, it may become impossible to distinguish the
correct entry from the incorrect one.
(5) Never remove
a page from the notebook. Draw diagonal lines across any page that is to be
disregarded. Provide a brief rationale for disregarding the page.
Notebook Format
** The
instructor should be consulted concerning the format to be used in keeping the laboratory
notebook.
** In one
convention, data and observations are recorded on consecutive pages as they
occur.
** The
completed analysis is then summarized on the next available page spread (that
is, left- and right-facing pages).
** As shown in the
following Figure:
** The first of
these two facing pages should contain the following entries:
(1) The title
of the experiment (The Gravimetric Determination of Chloride).
(2) A brief
statement of the principles on which the analysis is based.
(3) A complete
summary of the weighing, volumetric, and/or instrument response
data needed to
calculate the results.
(4) A report of
the best value for the set and a statement of its precision.
** The second
page should contain the following items:
(1) Equations
for the principal reactions in the analysis.
(2) An equation
showing how the results were calculated.
(3) A summary
of observations that appear to bear on the validity of a particular result or
the analysis as a whole. Any such entry must have been originally recorded in the
notebook at the time the observation was made.
Reference: Fundamentals of analytical chemistry / Douglas A. Skoog, Donald M. West, F. James Holler, Stanley R. Crouch. (ninth edition) , 2014 . USA
Reference: Fundamentals of analytical chemistry / Douglas A. Skoog, Donald M. West, F. James Holler, Stanley R. Crouch. (ninth edition) , 2014 . USA
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