Practical proofs of chemical laws. A course of experiments upon the combining proportions of the chemical elements

Vaughan Cornish

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• Chemistry
• Experiment

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• Publié par: les_archives_du_savoir
• Nombre de lectures: 6
• Langue: English
• Poids de l'ouvrage: 10 Mo

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PRACTICAL PROOFS
OF
CHEMICAL LAWS
VAUGHAN CORNISH
CD^RARY
OF THE
"v OF CALIFORNIA.CHEMICAL LAWSPRACTICAL PROOFS
OF
CHEMICAL LAWS
A COURSE OF EXPERIMENTS
UPON THE COMBINING PROPORTIONS OF
THE CHEMICAL ELEMENTS
BY
VAUGHAN' M.SC.CORNISH,
ASSOCIATE OF THE OWENS MANCHESTERCOLLEGE,
LONDON
AND CO.LONGMANS, GREEN,
NEWAND YORK
1895
All reserved-rightsPREFACE
THESE moreexperimental proofs (or properly
*
' rv
-x
of laws were undertakenverifications] quantitative"*
after the of theby qualitativepupils composition
substances had beenprincipal employed carefully
dealt with in the lecture course.accompanying
Practical onwent side side with thePhysics by
course.practical chemistry
The whose results are in thepupils quoted
text were between twelve andmostly eighteen years
of A book of results was so eachthatage. kept
could his results with others obtainedpupil compare
under similar conditions.
The had hour theat a time inpupils \\
and attended twice a week.laboratory,vi Preface
I have not been satisfied with quantitative
unless results in theexperiments they yield good
of the teacher but of thenothands, only pupils.
The in the text are thoseresults obtainedquoted
theby pupils.
I am not aware that a standard assatisfactory
to the for such hasaccuracy required experiments
been laid down. Within I cent, isper certainlyyet
the standard to somebutsufficient, may vary
nature of the law orextent to theaccording
investigated.problem
the standard is best determined byPerhaps
historical for the of a scienceconsiderations, history
the learner. If the canis recapitulated by pupil
a law to such a of asdegree approximationverify
first served to convince the scientific world of its
he be satisfied with his work.truth, generallymay
I have in the text the results of earlyquoted
side side with those ob-historic experiments by
in thesetained earlyby pupils. Although experi-
error is often there is lessments the large, yet
the learner havedifference than may supposedviiPreface
between the of theaccuracy first approximations
which have obtained the assent of theprovisional
scientific world at the and towards thebeginning
end of the nineteenth century, respectively.
As far as no numerical whetherdata,possible
chemical or were assumed. The densityphysical,
of inand the weighthydrogen proportion by
are neitherwhich and combinehydrogen oxygen
assumed nor determined in these experimental
verifications of the ofLaws Combining Proportions.
It is not that shouldequivalent weightsnecessary
be of and thereferred to that experi-hydrogen,
same asments cannot be done with the accuracy
is attainable in the case of other elements.
isThe use of atomic and molecular formulae
inadmissible in an examination of the facts upon
is based.which the atomic and molecular theory
have thereforeChemical and formula;equations
been excluded.
The course I suitable for first-year'sis, believe,
for the formsstudents at as well as uppercolleges
of schools.viii
Preface
I have to valuableacknowledge suggestions
received from other chemists while this course was
in thanks are due morepreparation. My particu-
to Dr. B. of the Yorkshirelarly J. COHEN, College,
and to Mr.Leeds, G. ofSTALLARD, Rugby.
VAUGHAN CORNISH.
August 1895.