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The use of apparatus is, of course, indispensable if the student is thus to study phenomena instead of descriptions ofphenomena, and the use of apparatus, by himself, is with-out doubt t

MENRV H, CLAPK & CO., BOSTOK.

PREFACE.

Ik an Ekimeiitary Chemistry, written in 1872, it was my piupose to give a short c<.)iirfie, for l)eginners, in ivhit'h the experimenial evidence,on whieli LJie most fimdaniental parts

ofthe science rested, should take the place ofminnle details aild advanced theoretical discussions, hoping in this way to

encourage the study ofclicmistryViy experimcTitinstead ofby booksalone,a,swass<jmuchthecustomat tliatday A Student's Guide, printed for the use ofmy classes in 1878, contained a course introductory to qualitative analysis, giving the student nothing but an outline of experiments He was expected

to make the experiments, to observe and describe iiis own results, and from these to construct for himselfa plan for the detection ofthe metals I nowcombine the leading ideas of thosetwobooks, and offer to myfellow-teachei-sanewvolume,

in which they are more fullydeveloped in ways suggested by

the unbroken experience of the intervening years

Chemistryas a bravich ofstudyin theschools has two great merits happily combined One is to bo found in the kind of

knowledge it oifera, and the other in the peculiar mental

training it affords. Of these the latter ia certainly not the

much in proportion to what he knows, as in proportion to

what he can dowith his knowledge Hence a chief purpose

fS

of tlie stndyof elementary chemistry in schools is to educate

the mind by giving it the right kind of exercise in tlieuse of

its powers,

I have therefore tried to make a, judicious selection ofthe

most fundamental facts and principles of chemistry, and to

present thesein such a waytliat the student must constantly

use his senses to discover facts, his reason in drawing correct

inferencesfrom the data he collects, and good English in

ex-pressing accurately what he sees and thinks

I know ofhut one way to teach a student howto acq^uire

areal knowledge ofnature, and that is,tofix hismind

habit-ually on things and events brought under hia own eye, and

directhimtothe discoveryoffacts andprinciples for himself

The use of apparatus is, of course, indispensable if the

student is thus to study phenomena instead of descriptions

ofphenomena, and the use of apparatus, by himself, is

with-out doubt the method which is most certain to stimulatehis

mind to tlie gieafest activity. Laboratory stndy forstudents

in high schouls is rapidlygrowing in favor, butunfortunately,

in many schools where chemistry istaught, the difflculties in

study of phenomena, hy esperiments, instead ofwhat

some-liody has said about phenomena in books

I have therefore tried to construct a course ofexperiments

suited to the use ofthe beginner, at his laboratory desk, and

to the use ofthe teacher for his class of beginners, where

ofreach

The studyofany subject by experimentcombines two kinds

of exercise; mechanical and menial operations go hand in

hand On this account experimental investigation is a

lo for heghiners is to make one or the other, the mechanical

or themental processes, predominate inour elementary course

of instruction Then which shall it be? The mechanical of

coursestands first, inonesense,for therewillbenophenomena

to study until apparatus is selected and arranged to exhibit

them But, on the other hand, a wise selection of apparatus and conditions cannot be made by one who has not already acquiredsomeskill intracingtherelations of causeand effect,

and some experience in the application of experimental methods I think we should first cultivate the power to

observe exhaustively and to detect relations,—that we should

makethe mentalmore prominent than themechanical in the

elementary study ofchemistry Accordingly:

In this courae of experiments the mechanical operations

are described in quite minute details. Exactly what is to he

for a time withheld Exceptions to this plan will be found

in the description of processes which are simply means to

secure conditions,and inthe statement offacts which may be needed for immediate use. But in general the phenomena whioli hold the chemistry of substances or pi-ocesses are left

for the student to discover See, for example, page 35, or

pages 85, 86.

Iknowthat muchstress is, i>ymany,laidupon the industrial

value of an instrument-making course in chemistry But it seems to me that the study of chemistry is not primarily to teacli mechanics, and that the use of toolsand the po.ssession

ofmechanical ingenuity am be better acquiredin the

indus-trial school or workshop, where these are the specific aims, than in the laboratory of the high school or academy, where

sake of mental

VI PREFACE. ,! PREFACE vn

the chief purpose Home-itiade apparatus is not to be

de-spised, butlohegreatly respected,where nothingbettercanbe

had, for miicli can be done with the most common utensils,

such as bottles, fruit-jai's, lea-saiiccrs, and oyster-cans But

certainlyheginncrscan do Vietterworkwith good facililiesthan

with poor ones And wliile there'is so much in the market

whieh is atonce scientificand inexpensive, the student sliould

be tanght to reach more accurate resulls tlian are otherwise

possible liy tlie use of it. Productive ingenuity and skill

must be founded on exactknowledge and clear thinking; they

cannot precede these. Therefore

Tlie apparatus called for in this course has been selected

from tliatwhich is madefor, aiid appiovedby, cheniists. The

pieces are neat, simple, easily put together,always inmarket,

and ascheapaspossible forgoodscientific ^vork. (See

Appen-dix, Fig 69.)

Abrief summary of the most importantfactsand principles

follows the e :« pel- imentalwork,by whichthestudentcan chock

and correct his results. In this sunmiary will be found the

information which should be acquired by beginnei's in

cheni-istry 1 have tried to include in it onlysuch things as will be

ofmost value to tlie many who will finish the studyof

lay afoundation for college work "Not liowmuch we know

is the best question,but how we have gotwhatwe know,and

what we can do with it, and, above all, wliat it lias made of

us."—J P.Lesue,

It is notwell to undertake toomuch It is not bestto have

the student's text-book burdened with matter which he is not

expected to master Thereis more educationtobe gainedby

extending the search for facts into other volumes than by

,i,tofexperiments, huthave.vied tomake ajud.cousseleohon,

Si in^hat a few typical ones well made and thoroughly studied^are far more useful than a larger number would be

f.w experiments In the

treatmentof a subjectmaybe seen by

Teferrin"to

"Substitution;' pp.10-31:

"Decompositionofmtnc acid," PP-02-95; or"ailorides," pp, 141-145,

Additionalwork isbetter whenprovidedbyteacliers forsuch

would make such work partake of the nature ofresearchas

be answered by his ownexperiments,or two substances wh(^e mutual reactions and results he is directed to investigate, or

asinglebody wliose propertieshe is asked tostudyandreport

Some work oftliis kind I have given under the headof "Ex-ercises." (See, for examples,pp.39, 82, 100.)

JText in value to research in the laboratory stands research

the results of his study, wilh apparatusau<l thetext-book, the

nucleus around which to group other facts, a center from which to extend his knowledge From the following works

the teacher can select abundant materialsfor this exercise, in

kind and quantity suited to the varying wants of different Individuals orofsuccessiveclasses, Buckley's "Short History

of Natural Science." Wnrtz' "History of Chemical Theory."

Wurt7.' "Atomic Tlicory." Cooky's "Xew Text-Book of

Chemistry," Cooke's "New Chemistry." Remsen's "Or-ganic Chemistry." Remsen's "Theoretical Chemistry."

Eos-coe and Schorlemmer's "Treatise on Chemistry." Frcsenius'

"Qualitative Analysis." Douglas Mid Prescott's "Qualitative

Analysis-"

vm PREFACE.

I have in al) case, rejected cbngorou experiment,

hat I

Im-e n, n,any ca.es devi.e,J

simple,safe, and oifioiem w.vs

to

for e.aniple

Hydrogen, pp. 29,30, and

Chlorine, pp 138 1S9

'

The wood-ents whioh represent the experiment, are, with

a single exception Fig. 23, made fi-onr the photographs or

.l™g.oi theapparatusin actualuse. For the elected eut

wh.ch :„ustrate the

description, of hi.ioncal or

indn^t^i work, r am unable to give the credit which i. due to their

CONTENTS.

OBSBEVATION AND EXPERIMENT.

rAOR Ch«niistrj'! OhBcrvation; experiment; way to stii<ly 9

CHEMICAL CHANGES.

Decompositioni combinatiaii; substitution; double

decom-position; heat and cheniical action; electricity and chemical action; liglit and chemical action 13

Hydrogen: Preparation of; properties of; cause of the explosion of; water a jnoduct ofits combustion; heat a

Oxygen: Preparationof; properties of; chemical actions of; occurrenceof; allotropisni of; ozone 33 Exercises: Experimentalstudyofchemical changes - - 3!)

CHEMISTRY OF COMBUSTION.

Bnrningofa candle; burningofothersubstances; material products; heat also a product; light also a product;

CHEMISTRY OF WATEB.

Analysis and synthesis; analysis ofwater; composition of water by weight; percentage composition; composition

by volume; constant composition of water; constant composition ofotlier compounds; the law of constant composition; wrter in nature; solvent poiver ofwater drinking watei's ; mineral ^valers ; elfect of cold on

Exercises: Experimental hivestigations 03

2 CONTENTS.

CHEMISTRY OP THE ATMOSPHERE.

Liwoisier'a t.'xj)eii]us;[it ; oxygen removed IVoiii iur by

Nitrog'eii: I'lviwratioii of; properties ol'; Am: imalysis

of; composiiioiL of; a mixture; tliliiit^ioii ofgases - 66

RcHpiratioii: Of unimals; produces cliaiiges in air

'Exercises: Investisjiitious—llm action of siilpliuvio on

oxaliu acid anil Llie action ol' pliosplioriis on air 82

COMPOUNDS OP NITROGEN, HYDROOEN, AND OXYGEN.

Oliicc of nitrogen in the iiir; chiiriictcrof the uomjioiuids

Aiiiiuoiiiii: i'roihiction of ammonia; the nascent state;

amnionic ingas-works; jiroparalioii of ammonia;

prop-ertiesofammonia; itsactiononthe acids; composition

Witric At'id: OccuiTeiuic of, in iiiitim]; made from

Kodiuni nitrate; proporlicK iii'; ilccompoi-ition of; tlio

Nitrog'on Oxides: .Stn<ly iif tlio decomposition ofnitric

acid bycopper; proofthatairtakespartinthe action

the several products; nitrous oxide; five nitrogen

oxides; the law of multiple proportions; combining

Exercises: Investigation oftests I'S

THE COMPOSITION OF PLANTS,

Decomposition ofwood by heat; constituent.sof plants- 101

Carbon: Source of carbon in plants; eharcoal-making

lamp-l>lack; action of charcoal on gases; action of

charcoal on colors; action of charcoal on oxides; the

FACr.

« .lio-vUle: rrepju-alion of;

properties of; carbon

*^^;rx'r - ou,i of carbon and hydrogen

;

^^^

nietliano

ELEMENTS, MOLECDLES, AND ATOMS.

'"

mdaTomic weights; thro,fonns ofmatter; focts a ,

!„d theories, to bo carefully ch.tu.gvnshed. Mole^ cuLES- some fael.'^ about the ex pans,on ot gases, the

Seorv'; chemical changes are changes m molecules;

^oul "nniltiple proportions'' explamed; atom.c theory; symbols; fonnula.s; atomic weights; molecular

^^^

weights; reactions

ACIDS EASES AND SALTS

Acids; salts; hydroxides; reaction of acid, and hases;^^ neutralcompounds

Chemical names: or acids; ofsalts; ofbases - 135

CHLORINE AND THE CHLORIDES.

Discovery of chlorine; preparation and propertip^ of

"""IZL; bleaching; the r,n.OH,.Ks; ^'^ - js by

chlorinewater; chloridesbybydrochloncae.d

;

chlo,ides

by aqua regia; two chlorides of one metal; yi.rogek

SZ>e: ?.eparation of; composition o^

-. of volume; composition ofcompounds the

J''^«

"" ume"law deduced; test for ehlori,.eandthe chloride . 138

fluorine

their hydrogen e<,mpounds; relation of atomicweight.,

^^^

to properties

Exercises: Study of tet^ls

SULPHUR AND ITS COMPOUNDS.

Native sulphur and snlpbides; preparation of sulphn,'; properties of snlphnr; artil^clal sulphides;

inimo^E^

xu CONTENTS.

PAGE The Sulphur Group: Soleiiiuni ; tellurium; hydrogen

Sulphurous Oxide and Acid: Preparation of

siilpliur-ous oxiilc; properties ot sulpliiiroiis oxick; sulphurous

Sulpliuric Acid and tlie Sulphates; Properties of

the aeiil; upcs of the iieiil; te^t for the acid;

manufac-ture of the acid; the sulphatejs: svilphatcs by action

of the iwid on metals; hyaetioii of the aeid on bases;

two sulphates of the same metal; othersulpburacids 1(56

Exercises: Investigation oftests 173

PHOSPHORUS AND THE NITROGEN GROUP.

Discovery of ])hos]>lioriis; properties; red phosphorus

matches; phosphorusoxidesand acids; tlie phosphates;

manufacture ofphosphorus 175

Arsenicj: Arsenous oxide; arsenic oxide; arsenic and

com-pounds; relation of atomic weights to properties . 182

SlIilCON, AND THE CAEBON GROUP.

Silicon: Its oxide; the cakbon ghoup; members; their

hydrogen compounds; tlieir oxygen compounds; tlie

Boron: The element; borax; boric acid; no hydrogen

VALENCE.

A difference in atnnis; valence defined; substitution

go\'crned by valence; the valence of horoii; valence

useful in study of reactions; valenee of an element

n

CONTENTS.

THE METALS.

j

What is a metal? number and abundance of the metals

occurrence in nature

Xlll

192

THE POTASSIUM GROUP.

occurrence in nature; potassium carbonate; potassnmi hydroxide; experiments hi the preparation of some

_^^ other salts ; liame test

Sodium: Description of; occurrence in nature; sodium carbonate; sodium hydroxide; Hame test; study of reaction ofsodium eoniponnds

Aiuniouium: Facts about ammonia; coniparison of

formulas; the hypothetical metal; its salts; the

sul-phides; studyof reactions ofammonium compounds - JOl

The Potassium Group: Names ofmembei-s;

compari-^^

son of properties

THE CALCIUM GROUP.

Calcium: Themetal; iU occurrence in nature; effectof heat on the carbonate; effectof acidson the carbonate

pre-pare the insoluble compounds; to prepare the soluble

^^

compounds

The Calcium Group: Xames of t],c members; com-parison of atomic weights and properties; study of

characteristic reactions; flame colors

METALS OF THE ZINC GROUP.

Magnesium: The metal; its compounds; studyof

Zinc: The metal; manufacture of; uses of; compoiinds

of; preparation ofin^luble compounds, and study of

THE IRON GROUP.

PAQE

maii-ganate aniJ jjerniaiigiiimte ; Ktndy of reactions with

manganese salts; cobalt; uickrl 217

the Ores; east-iron; the three forms ofiron;

manofac-ture of wrought-iron; manufaeture of steel, Bessemer

process; cementation; compoundsofiron; tivo classes;

the two chlorides; distinctive reactions for the two

Clironiiuin; Themetal;itsore; thepotassiumchromate;

the dichromate; reactions of chromium salts 229

The Iron Oroup: comparison of properties 231

ALUMINUM.

Tlie metal; alum; aluminum oxide; study of reactions

THE ANTIMONY GROOP.

Antimony: 'I'lie metal; alloys of; bismuth; the

anti-mony group; the I'cactions of ai'sonie, antimony, and

Tin: Occurrence in nature; extraction from the ore

properties of the metal; compoimds of tin ; distinctive

reactionfortms:ind iucompounds; general reactions of

Ijcad: Occiirrencii in nature; extraction from the ore;

twomethods; lead oxides; leadcarbonate; reactions of

THE COPPER GKODP.

Copppp; Occurrence iji nature; extraction from ils'TJres;

properties of the metal; copper compounds; the

sul-phate; study ofreactionsof the salts ofcopper 347

PAOE

^

.v Occurrenceinnature; extraction fromits ore;

"^''Ses Of the n.etal; compounds of n.ercury; the

fj^rides; mercurous compounds; mercur.c com-pounds; study of reactions

Oliver- Occnrrence in nature;

extraction from its

sul-Se- extraction fromgalena; propertiesofthemetal,

S^und.ofsilver ; reactionsof thesalt, of Iver. . 254

GOLD AND PLATINUM.

-V Gold: Occurrence in nature; obtained hy ''washing"; obtained by "amalgamation"; properties of gold . .2-9 Platinum: Occurrence in nature; properties of

the

^^^^^

OLASSIPICATION.

Classes: How they are made; the classes of the non-metals founded on valence; metals not always classed

in tills way; more than one way to group the metals;

TheIfatm-al System; Cl.wsilication byatomic weights; Newland's discovery;MendelejeUsextension; thespiral

^^^

of elements; the vaciint places

s,>la-l^ilities ; analytical table drawn from the preceding

ex-perimentsin this com^e; howto find outwhat metal a

part; to name the salt; bint for further work; form

ofnotes

JM

268

ELEMFiXTARY CHHMISTRY.

In the stiuly ofChemistry we are tolearn some things

:ibout tlie ditfereut kinds of matter There are two ways

Tliese two ways of studying nature are ealled ohservution

and eypi'vlmpnt

Observation.

—

"WIk'u I look a.t something which is

goingon, and watch carefullyto secwliat happens, mj act

id anobservation To hiok at an olijei't so elojielythat we can see its shape, its color, and wliatever else is visible

about it, is an act of observation

If, for example, I desire to know as nuich as possible about a butterfly, the bestway to learn it is to catch the

what 1 see. The butterfiy would show mc thatit has four wings, six legs, two long haii'-like bodies (antenuEe) reach-ingforward fromits head with knobs upontheir ends, two

turn, and that the beautiful colors of its wings are due to

these facts I could learir byholding the insect inthe hand and lookingatit thoughtfully

obser-vation

10 OBSEEVAriON AND EXPERIMENT.

object iia 1 find it, I do soiiietluug to it to see howit will

behave or appeal' in ditferent conditions, this operation

is

an experiment

Will 5 ciibificentimeters ofwaterdissolve asmuch as 10

grains of granulated sugar? I cannot iind out by simply

looking at siigai' and water In order to leai'n what the

faet IS, I may put the two things together in the right

way, and if I do so I make an experiment Thus:

J'-x 2.—I take a tall glass cylinder,a, Pig. 1, which is

gi-aduated to measure cubic centimeters, and pour in water

Ke 1.

up to the 5 00, mark." I transfer this water to one of

the thin rouiiddwttoined cylinders, b, called a test-tube

I also weigh out 10 g. of grmiulated sugar= and put it

intothewater inthe tube i.« Inow warm tlie tubein the

flame of a Bunsen lamp, c. There is danger of breaking

the tubeif I heatit too suddenly, or too long in one spot,

' If uiie must set along witlinut a graduated cylhuier he maw

obtitii, 5 cc. very nearly by filling liis test-tulie one incii above tlie

rounded bottom Thetubeissupposedto be §- i.ich indiameter

= If one must got along witbout a balance, he caii obtain about

10g.of dry sugar by filling a teaspoontwite,

= Pold anarrowstrip ofpaperinto tl.e shapeofatrough andlav

this intheinbe,wliiolishould befield inaslantins position. Thedry

sugarwill slide safdydown thistrough insteadof clinging to thewet

walls of the tube.

OBSERVATION AND EXPERIMENT U

andto avoid this danger I move it slowly in the flaine to heatallsides evenly Whenthe liquid begins to boil I lift

thetube intothe hotairabove the flame, whereI can keep

ithot without boilingit too vigorously Iwatchtosee

"Whether the sugar remains, or becomes less and less.

If the liquid at length becomes, as it will, almost or quite transparent,we shallknowthat 5 ec. ofhotwater can dissolve 10 g. of sugar Iwill then stand the tube in the

tube-rack, and when it iscold I willlook againand sec

Whether5cc,of '/nldwater can holdthe 10g.in solution

Let us keepthis syrupfor use in another experiment The sap ofsome trees and the juices of some plants are

natural solutions of sugarin water, hut the quantity of sugar in 5 cc. of these

experiment could have first shown that

5 cc. of water can dissolve so much sugar as we have found it to do

But in experiments we often put things together in ways in which na^

ture never does For example, I wish

to know how sugar will behave in strong sulphuric acid.

Kature never putsthesetwo things together,and the only way I con find out how they will act in the presence of each other is to bring them together Thus

Ex.2.—I measure out 6 cc. of strong sulphuric acid

^vitlithe cylinder a. Fig 1, pouritinto an emptytest-tube,

then rinsethe cylinder and stand it on asmallplate Fig.2.

I now [lour the sugar syrup miule in the other experiment

to-gether, Ipourthe acid in a slender streaminto the syrup, andwatcli for evevy changethathappens Inotice

A change in color

Fie 2.