SOME SIMPLE ORGANIC COMPOUNDS
~Division of chemistry into organic and inorganic.~ Chemistry is usually
divided into two great divisions,--organic and inorganic. The original
significance of these terms was entirely different from the meaning
which they have at the present time.
1. _Original significance._ The division into organic and inorganic was
originally made because it was believed that those substances which
constitute the essential parts of living organisms were built up under
the influence of the life force of the organism. Such substances,
therefore, should be regarded as different from those compounds prepared
in the laboratory or formed from the inorganic or mineral constituents
of the earth. In accordance with this view organic chemistry included
those substances formed by living organisms. Inorganic chemistry, on the
other hand, included all substances formed from the mineral portions of
the earth.
In 1828 the German chemist Wöhler prepared urea, a typical organic
compound, from inorganic materials. The synthesis of other so-called
organic compounds followed, and at present it is known that the same
chemical laws apply to all substances whether formed in the living
organism or prepared in the laboratory from inorganic constituents. The
terms "organic" and "inorganic" have therefore lost their original
significance.
2. _Present significance._ The great majority of the compounds found in
living organisms contain carbon, and the term "organic chemistry," as
used at present, includes not only these compounds but all compounds of
carbon. _Organic chemistry_ has become, therefore, _the chemistry of the
compounds of carbon_, all other substances being treated under the head
of inorganic chemistry. This separation of the compounds of carbon into
a group by themselves is made almost necessary by their great number,
over one hundred thousand having been recorded. For convenience some of
the simpler carbon compounds, such as the oxides and the carbonates, are
usually discussed in inorganic chemistry.
~The grouping of compounds in classes.~ The study of organic chemistry is
much simplified by the fact that the large number of bodies included in
this field may be grouped in classes of similar compounds. It thus
becomes possible to study the properties of each class as a whole, in
much the same way as we study a group of elements. The most important of
these classes are the _hydrocarbons_, the _alcohols_, the _aldehydes_,
the _acids_, the _ethereal salts_, the _ethers_, the _ketones_, the
_organic bases_, and the _carbohydrates_. A few members of each of these
classes will now be discussed briefly.
THE HYDROCARBONS
Carbon and hydrogen combine to form a large number of compounds. These
compounds are known collectively as the _hydrocarbons_. They may be
divided into a number of groups or series, each being named from its
first member. Some of the groups are as follows:
METHANE SERIES
CH_{4} methane
C_{2}H_{6} ethane
C_{3}H_{8} propane
C_{4}H_{10} butane
C_{5}H_{12} pentane
C_{6}H_{14} hexane
C_{7}H_{16} heptane
C_{8}H_{18} octane
ETHYLENE SERIES
C_{2}H_{4} ethylene
C_{3}H_{6} propylene
C_{4}H_{8} butylene
BENZENE SERIES
C_{6}H_{6} benzene
C_{7}H_{8} toluene
C_{8}H_{10} xylene
ACETYLENE SERIES
C_{2}H_{2} acetylene
C_{3}H_{4} allylene
Only the lower members (that is, those which contain a small number of
carbon atoms) of the above groups are given. The methane series is the
most extensive, all of the compounds up to C_{24}H_{50} being known.
It will be noticed that the successive members of each of the above
series differ by the group of atoms (CH_{2}). Such a series is called an
_homologous series_. In general, it may be stated that the members of an
homologous series show a regular gradation in most physical properties
and are similar in chemical properties. Thus in the methane group the
first four members are gases at ordinary temperatures; those containing
from five to sixteen carbon atoms are liquids, the boiling points of
which increase with the number of carbon atoms present. Those containing
more than sixteen carbon atoms are solids.
~Sources of the hydrocarbons.~ There are two chief sources of the
hydrocarbons, namely, (1) crude petroleum and (2) coal tar.
1. _Crude petroleum._ This is a liquid pumped from wells driven into the
earth in certain localities. Pennsylvania, Ohio, Kansas, California, and
Texas are the chief oil-producing regions in the United States. The
crude petroleum consists largely of liquid hydrocarbons in which are
dissolved both gaseous and solid hydrocarbons. Before being used it must
be refined. In this process the petroleum is run into large iron stills
and subjected to fractional distillation. The various hydrocarbons
distill over in the general order of their boiling points. The
distillates which collect between certain limits of temperature are kept
separate and serve for different uses; they are further purified,
generally by washing with sulphuric acid, then with an alkali, and
finally with water. Among the products obtained from crude petroleum in
this way are the naphthas, including benzine and gasoline, kerosene or
coal oil, lubricating oils, vaseline, and paraffin. None of these
products are definite chemical compounds, but each consists of a mixture
of hydrocarbons, the boiling points of which lie within certain limits.
2. _Coal tar._ This product is obtained in the manufacture of coal gas,
as already explained. It is a complex mixture and is refined by the same
general method used in refining crude petroleum. The principal
hydrocarbons obtained from the coal tar are benzene, toluene,
naphthalene, and anthracene. In addition to the hydrocarbons, coal tar
contains many other compounds, such as carbolic acid and aniline.
~Properties of the hydrocarbons.~ The lower members of the first two
series of hydrocarbons mentioned are all gases; the succeeding members
are liquids. In some series, as the methane series, the higher members
are solids. The preparation and properties of methane and acetylene have
been discussed in a previous chapter. Ethylene is present in small
quantities in coal gas and may be obtained in the laboratory by
treating alcohol (C_{2}H_{6}O) with sulphuric acid:
C_{2}H_{6}O = C_{2}H_{4} + H_{2}O.
Benzene, the first member of the benzene series, is a liquid boiling at
80°.
The hydrocarbons serve as the materials from which a large number of
compounds can be prepared; indeed, it has been proposed to call organic
chemistry _the chemistry of the hydrocarbon derivatives_.
~Substitution products of the hydrocarbons.~ As a rule, at least a part of
the hydrogen in any hydrocarbon can be displaced by an equivalent amount
of certain elements or groups of elements. Thus the compounds CH_{3}Cl,
CH_{2}Cl_{2}, CHCl_{3}, CCl_{4} can be obtained from methane by
treatment with chlorine. Such compounds are called _substitution
products_.
~Chloroform~ (CHCl_{3}). This can be made by treating methane with
chlorine, as just indicated, although a much easier method consists in
treating alcohol or acetone (which see) with bleaching powder.
Chloroform is a heavy liquid having a pleasant odor and a sweetish
taste. It is largely used as a solvent and as an anæsthetic in surgery.
~Iodoform~ (CHI_{3}). This is a yellow crystalline solid obtained by
treating alcohol with iodine and an alkali. It has a characteristic odor
and is used as an antiseptic.
ALCOHOLS
When such a compound as CH_{3}Cl is treated with silver hydroxide the
reaction expressed by the following equation takes place:
CH_{3}Cl + AgOH = CH_{3}OH + AgCl.
Similarly C_{2}H_{5}Cl will give C_{2}H_{5}OH and AgCl. The compounds
CH_{3}OH and C_{2}H_{5}OH so obtained belong to the class of substances
known as _alcohols_. From their formulas it will be seen that they may
be regarded as derived from hydrocarbons by substituting the hydroxyl
group (OH) for hydrogen. Thus the alcohol CH_{3}OH may be regarded as
derived from methane (CH_{4}) by substituting the group OH for one atom
of hydrogen. A great many alcohols are known, and, like the
hydrocarbons, they may be grouped into series. The relation between the
first three members of the methane series and the corresponding alcohols
is shown in the following table:
CH_{4} (methane) CH_{3}OH (methyl alcohol).
C_{2}H_{6} (ethane) C_{2}H_{5}OH (ethyl alcohol).
C_{3}H_{8} (propane) C_{3}H_{7}OH (propyl alcohol).
~Methyl alcohol~ (_wood alcohol_) (CH_{3}OH). When wood is placed in an
air-tight retort and heated, a number of compounds are evolved, the most
important of which are the three liquids, methyl alcohol, acetic acid,
and acetone. Methyl alcohol is obtained entirely from this source, and
on this account is commonly called _wood alcohol_. It is a colorless
liquid which has a density of 0.79 and boils at 67°. It burns with an
almost colorless flame and is sometimes used for heating purposes, in
place of the more expensive ethyl alcohol. It is a good solvent for
organic substances and is used especially as a solvent in the
manufacture of varnishes. It is very poisonous.
~Ethyl alcohol~ (_common alcohol_) (C_{2}H_{5}OH). 1. _Preparation._ This
compound may be prepared from glucose (C_{6}H_{12}O_{6}), a sugar easily
obtained from starch. If some baker's yeast is added to a solution of
glucose and the temperature is maintained at about 30°, bubbles of gas
are soon evolved, showing that a change is taking place. The yeast
contains a large number of minute organized bodies, which are really
forms of plant life. The plant grows in the glucose solution, and in so
doing secretes a substance known as _zymase_, which breaks down the
glucose in accordance with the following equation:
C_{6}H_{12}O_{6} = 2C_{2}H_{5}OH + 2CO_{2}.
~Laboratory preparation of alcohol.~ The formation of alcohol and
carbon dioxide from glucose may be shown as follows: About 100
g. of glucose are dissolved in a liter of water in flask A
(Fig. 90). This flask is connected with the bottle B, which
is partially filled with limewater. The tube C contains solid
sodium hydroxide. A little baker's yeast is now added to the
solution in flask A, and the apparatus is connected, as shown
in the figure. If the temperature is maintained at about 30°,
the reaction soon begins. The bubbles of gas escape through the
limewater in B. A precipitate of calcium carbonate soon forms
in the limewater, showing the presence of carbon dioxide. The
sodium hydroxide in tube C prevents the carbon dioxide in the
air from acting on the limewater. The alcohol remains in the
flask A and may be separated by fractional distillation.
[Illustration: Fig. 90]
2. _Properties._ Ethyl alcohol is a colorless liquid with a pleasant
odor. It has a density of 0.78 and boils at 78°. It resembles methyl
alcohol in its general properties. It is sometimes used as a source of
heat, since its flame is very hot and does not deposit carbon, as the
flame from oil does. When taken into the system in small quantities it
causes intoxication; in larger quantities it acts as a poison. The
intoxicating properties of such liquors as beer, wine, and whisky are
due to the alcohol present. Beer contains from 2 to 5% of alcohol, wine
from 5 to 20%, and whisky about 50%. The ordinary alcohol of the
druggist contains 94% of alcohol and 6% of water. When this is boiled
with lime and then distilled nearly all the water is removed, the
distillate being called _absolute alcohol_.
~Commercial preparation of alcohol.~ Alcohol is prepared
commercially from starch obtained from corn or potatoes. The
starch is first converted into a sugar known as maltose, by the
action of _malt_, a substance prepared by moistening barley
with water, allowing it to germinate, and then drying it. There
is present in the malt a substance known as diastase, which has
the property of changing starch into maltose. This sugar, like
glucose, breaks down into alcohol and carbon dioxide in the
presence of yeast. The resulting alcohol is separated by
fractional distillation.
~Denatured alcohol.~ The 94% alcohol is prepared at present at a
cost of about 35 cents per gallon, which is about half the cost
of the preparation of methyl alcohol. The government, however,
imposes a tax on all ethyl alcohol which amounts to $2.08 per
gallon on the 94% product. This increases its cost to such an
extent that it is not economical to use it for many purposes
for which it is adapted, such as a solvent in the preparation
of paints and varnishes and as a material for the preparation
of many important organic compounds. By an act of Congress in
1906, the tax was removed from _denatured_ alcohol, that is
alcohol mixed with some substance which renders it unfit for
the purposes of a beverage but will not impair its use for
manufacturing purposes. Some of the European countries have
similar laws. The substances ordinarily used to denature
alcohol are wood alcohol and pyridine, the latter compound
having a very offensive odor.
~Fermentation.~ The reaction which takes place in the preparation
of ethyl alcohol belongs to the class of changes known under
the general name of fermentation. Thus we say that the yeast
causes the glucose to ferment, and the process is known as
alcoholic fermentation. There are many kinds of fermentations,
and each is thought to be due to the presence of a definite
substance known as an _enzyme_, which acts by catalysis. In
many cases, as in alcoholic fermentation, the change is brought
about by the action of minute forms of life. These probably
secrete the enzymes which cause the fermentation to take place.
Thus the yeast plant is supposed to bring about alcoholic
fermentation by secreting the enzyme known as zymase.
~Glycerin~ (C_{3}H_{5}(OH)_{3}). This compound may be regarded as derived
from propane (C_{3}H_{8}) by displacing three atoms of hydrogen by three
hydroxyl groups, and must therefore be regarded as an alcohol. It is
formed in the manufacture of soaps, as will be explained later. It is an
oily, colorless liquid having a sweetish taste. It is used in medicine
and in the manufacture of the explosives nitroglycerin and dynamite.
ALDEHYDES
When alcohols are treated with certain oxidizing agents two hydrogen
atoms are removed from each molecule of the alcohol. The resulting
compounds are known as aldehydes. The relation of the aldehydes derived
from methyl and ethyl alcohol to the alcohols themselves may be shown as
follows:
Alcohols {CH_{3}OH Corresponding aldehydes {CH_{2}O
{C_{2}H_{5}OH {C_{2}H_{4}O
The first of these (CH_{2}O) is a gas known as formaldehyde. Its aqueous
solution is largely used as an antiseptic and disinfectant under the
name of _formalin_. Acetaldehyde (C_{2}H_{4}O) is a liquid boiling at
21°.
ACIDS
Like the other classes of organic compounds, the organic acids may be
arranged in homologous series. One of the most important of these series
is the _fatty-acid series_, the name having been given to it because
the derivatives of certain of its members are constituents of the fats.
Some of the most important members of the series are given in the
following table. They are all monobasic, and this fact is expressed in
the formulas by separating the replaceable hydrogen atom from the rest
of the molecule:
H·CHO_{2} formic acid, a liquid boiling at 100°.
H·C_{2}H_{3}O acetic acid, a liquid boiling at 118°.
H·C_{3}H_{5}O_{2} propionic acid, a liquid boiling at 140°.
H·C_{4}H_{7}O_{2} butyric acid, a liquid boiling at 163°.
H·C_{16}H_{31}O_{2} palmitic acid, a solid melting at 62°.
H·C_{18}H_{35}O_{2} stearic acid, a solid melting at 69°.
~Formic acid~ (H·CHO_{2}). The name "formic" is derived from the Latin
_formica_, signifying ant. This name was given to the acid because it
was formerly obtained from a certain kind of ants. It is a colorless
liquid and occurs in many plants such as the stinging nettles. The
inflammation caused by the sting of the bee is due to formic acid.
~Acetic acid~ (H·C_{2}H_{3}O_{2}). Acetic acid is the acid present in
vinegar, the sour taste being due to it. It can be prepared by either of
the following methods.
1. _Acetic fermentation._ This consists in the change of alcohol into
acetic acid through the agency of a minute organism commonly called
mother of vinegar. The change is represented by the following equation:
C_{2}H_{5}OH + 2O = HC_{2}H_{3}O_{2} + H_{2}O.
The various kinds of vinegars are all made by this process. In the
manufacture of cider vinegar the sugar present in the cider first
undergoes alcoholic fermentation; the resulting alcohol then undergoes
acetic fermentation. The amount of acetic acid present in vinegars
varies from 3 to 6%.
2. _From the distillation of wood._ The liquid obtained by heating wood
in the absence of air contains a large amount of acetic acid, and this
can be separated readily in a pure state. This is the most economical
method for the preparation of the concentrated acid.
Acetic acid is a colorless liquid and has a strong pungent odor.
Many of its salts are well-known compounds. Lead acetate
(Pb(C_{2}H_{3}O_{2})_{2}) is the ordinary _sugar of lead_. Sodium
acetate (NaC_{2}H_{3}O_{2}) is a white solid largely used in making
chemical analyses. Copper acetate (Cu(C_{2}H_{3}O_{2})_{2}) is a blue
solid. When copper is acted upon by acetic acid in the presence of air a
green basic acetate of copper is formed. This is commonly known as
verdigris. All acetates are soluble in water.
~Butyric acid~ (H·C_{4}H_{7}O_{2}). Derivatives of butyric acid are
present in butter and impart to it its characteristic flavor.
~Palmitic and stearic acids.~ Ordinary fats consist principally of
derivatives of palmitic and stearic acids. When the fats are heated with
sodium hydroxide the sodium salts of these acids are formed. If
hydrochloric acid is added to a solution of the sodium salts, the free
palmitic and stearic acids are precipitated. They are white solids,
insoluble in water. Stearic acid is often used in making candles.
~Acids belonging to other series.~ In addition to members of the
fatty-acid series, mention may be made of the following well-known
acids.
~Oxalic acid~ (H_{2}C_{2}O_{4}). This is a white solid which occurs in
nature in many plants, such as the sorrels. Its ammonium salt
((NH_{4})_{2}C_{2}O_{4}) is used as a reagent for the detection of
calcium. When added to a solution of a calcium compound the white,
insoluble calcium oxalate (CaC_{2}O_{4}) precipitates.
~Tartaric acid~ (H_{2}·C_{4}H_{4}O_{6}). This compound occurs either in a
free state or in the form of its salts in many fruits. The potassium
acid salt (KHC_{4}H_{4}O_{6}) occurs in the juice of grapes. When the
juice ferments in the manufacture of wine, this salt, being insoluble in
alcohol, separates out on the sides of the cask and in this form is
known as argol. This is more or less colored by the coloring matter of
the grape. When purified it forms a white solid and is sold under the
name of cream of tartar. The following are also well-known salts of
tartaric acid: potassium sodium tartrate (Rochelle salt)
(KNaC_{4}H_{4}O_{6}), potassium antimonyl tartrate (tartar emetic)
(KSbOC_{4}H_{4}O_{6}).
~Cream of tartar baking powders.~ The so-called cream of tartar
baking powders consist of a mixture of cream of tartar,
bicarbonate of soda, and some starch or flour. When water is
added to this mixture the cream of tartar slowly acts upon the
soda present liberating carbon dioxide in accordance with the
following equation:
KHC_{4}H_{4}O_{6} + NaHCO_{3} = KNaC_{4}H_{4}O_{6} + H_{2}O +
CO_{2}.
The carbon dioxide evolved escapes through the dough, thus
making it light and porous.
~Citric acid~ (H_{3}·C_{6}H_{5}O_{7}). This acid occurs in many fruits,
especially in lemons. It is a white solid, soluble in water, and is
often used as a substitute for lemons in making lemonade.
~Lactic acid~ (H·C_{3}H_{5}O_{3}). This is a liquid which is formed in the
souring of milk.
~Oleic acid~ (H·C_{18}H_{33}O_{2}). The derivatives of this acid
constitute the principal part of many oils and liquid fats. The acid
itself is an oily liquid.
ETHEREAL SALTS
When acids are brought in contact with alcohols under certain conditions
a reaction takes place similar to that which takes place between acids
and bases. The following equations will serve as illustrations:
KOH + HNO_{3} = KNO_{3} + H_{2}O,
CH_{3}OH + HNO_{3} = CH_{3}NO_{3} + H_{2}O.
The resulting compounds of which methyl nitrate (CH_{3}NO_{3}) may be
taken as the type belong to the class known as _ethereal salts_, the
name having been given them because some of them possess pleasant
ethereal odors. It will be seen that the ethereal salts differ from
ordinary salts in that they contain a hydrocarbon radical, such as
CH_{3}, C_{2}H_{5}, C_{3}H_{5}, in place of a metal.
~The nitrates of glycerin~ (_nitroglycerin_). Nitric acid reacts with
glycerin in the same way that it reacts with a base containing three
hydroxyl groups such as Fe(OH)_{3}:
Fe(OH)_{3} + 3HNO_{3} = Fe(NO_{3})_{3} + 3H_{2}O,
C_{3}H_{5}(OH)_{3} + 3HNO_{3} = C_{3}H_{5}(NO_{3})_{3} + 3H_{2}O.
The resulting nitrate (C_{3}H_{5}(NO_{3})_{3}) is the main constituent
of _nitroglycerin_, a slightly yellowish oil characterized by its
explosive properties. Dynamite consists of porous earth which has
absorbed nitroglycerin, and its strength depends on the amount present.
It is used much more largely than nitroglycerin itself, since it does
not explode so readily by concussion and hence can be transported with
safety.
~The fats.~ These are largely mixtures of the ethereal salts known
respectively as olein, palmitin, and stearin. These salts may be
regarded as derived from oleic, palmitic, and stearic acids
respectively, by replacing the hydrogen of the acid with the glycerin
radical C_{3}H_{5}. Since this radical is trivalent and oleic, palmitic,
and stearic acids contain only one replaceable hydrogen atom to the
molecule, it is evident that three molecules of each acid must enter
into each molecule of the ethereal salt. The formulas for the acids and
the ethereal salts derived from each are as follows:
HC_{18}H_{33}O_{2} (oleic acid)
C_{8}H_{6}(C_{18}H_{33}O_{2})_{3}, (olein)
HC_{16}H_{31}O_{2} (palmitic acid)
C_{3}H_{5}(C_{16}H_{31}0_{2})_{3} (palmitin)
HC_{18}H_{35}O_{2} (stearic acid)
C_{3}H_{5}(C_{18}H_{35}O_{2})_{3} (stearin)
Olein is a liquid and is the main constituent of liquid fats. Palmitin
and stearin are solids.
~Butter fat and oleomargarine.~ Butter fat consists principally of olein,
palmitin, and stearin. The flavor of the fat is due to the presence of a
small amount of butyrin, which is an ethereal salt of butyric acid.
Oleomargarine differs from butter mainly in the fact that a smaller
amount of butyrin is present. It is made from the fats obtained from
cattle and hogs. This fat is churned up with milk, or a small amount of
butter is added, in order to furnish sufficient butyrin to impart the
butter flavor.
~Saponification.~ When an ethereal salt is heated with an alkali a
reaction expressed by the following equation takes place:
C_{2}H_{5}NO_{3} + KOH = C_{2}H_{5}OH + KNO_{3}.
This process is known as _saponification_, since it is the one which
takes place in the manufacture of soaps. The ordinary soaps are made by
heating fats with a solution of sodium hydroxide. The reactions
involved may be illustrated by the following equation representing the
reaction between palmitin and sodium hydroxide:
C_{3}H_{5}(C_{16}H_{31}O_{2})_{3} + 3 NaOH
= 3 NaC_{16}H_{31}O_{2} + C_{3}H_{5}(OH)_{3}.
In accordance with this equation the ethereal salts in the fats are
converted into glycerin and the sodium salts of the corresponding acids.
The sodium salts are separated and constitute the soaps. These salts are
soluble in water. When added to water containing calcium salts the
insoluble calcium palmitate and stearate are precipitated. Magnesium
salts act in a similar way. It is because of these facts that soap is
used up by hard waters.
ETHERS
When ethyl alcohol is heated to 140° with sulphuric acid the reaction
expressed by the following equation takes place:
2C_{2}H_{5}OH = (C_{2}H_{5})_{2}O + H_{2}O.
The resulting compound, (C_{2}H_{5})_{2}O, is ordinary ether and is the
most important member of the class of compounds called _ethers_.
Ordinarily ether is a light, very inflammable liquid boiling at 35°. It
is used as a solvent for organic substances and as an anæsthetic in
surgical operations.
KETONES
The most common member of this group is acetone (C_{3}H_{6}O), a
colorless liquid obtained when wood is heated in the absence of air. It
is used in the preparation of other organic compounds, especially
chloroform.
ORGANIC BASES
This group includes a number of compounds, all of which contain nitrogen
as well as carbon. They are characterized by combining directly with
acids to form salts, and in this respect they resemble ammonia. They
may, indeed, be regarded as derived from ammonia by displacing a part or
all of the hydrogen present in ammonia by hydrocarbon radicals. Among
the simplest of these compounds may be mentioned methylamine
(CH_{3}NH_{2}) and ethylamine (C_{2}H_{5}NH_{2}). These two compounds
are gases and are formed in the distillation of wood and bones. Pyridine
(C_{5}H_{6}N) and quinoline (C_{9}H_{7}N) are liquids present in small
amounts in coal tar, and also in the liquid obtained by the distillation
of bones. Most of the compounds now classified under the general name of
_alkaloids_ (which see) also belong to this group.
CARBOHYDRATES
The term "carbohydrate" is applied to a class of compounds which
includes the sugars, starch, and allied bodies These compounds contain
carbon, hydrogen, and oxygen the last two elements generally being
present in the proportion in which they combine to form water. The most
important members of this class are the following:
Cane sugar C_{12}H_{22}O_{11}.
Milk sugar C_{12}H_{22}O_{11}.
Dextrose C_{6}H_{12}O_{6}.
Levulose C_{6}H_{12}O_{6}.
Cellulose C_{6}H_{10}O_{5}.
Starch C_{6}H_{10}0_{5}.
~Cane sugar~ (C_{12}H_{22}O_{11}). This is the well-known substance
commonly called sugar. It occurs in many plants especially in the sugar
cane and sugar beet. It was formerly obtained almost entirely from the
sugar cane, but at present the greatest amount of it comes from the
sugar beet. The juice from the cane or beet contains the sugar in
solution along with many impurities. These impurities are removed, and
the resulting solution is then evaporated until the sugar crystallizes
out. The evaporation is conducted in closed vessels from which the air
is partially exhausted. In this way the boiling point of the solution is
lowered and the charring of the sugar is prevented. It is impossible to
remove all the sugar from the solution. In preparing sugar from sugar
cane the liquors left after separating as much of it as possible from
the juice of the cane constitute ordinary molasses. Maple sugar is made
by the evaporation of the sap obtained from a species of the maple tree.
Its sweetness is due to the presence of cane sugar, other products
present in the maple sap imparting the distinctive flavor.
When a solution of cane sugar is heated with hydrochloric or other
dilute mineral acid, two compounds, dextrose and levulose, are formed in
accordance with the following equation:
C_{12}H_{22}O_{11} + H_{2}O = C_{6}H_{12}O_{6} + C_{6}H_{12}O_{6}.
This same change is brought about by the action of an enzyme present in
the yeast plant. When yeast is added to a solution of cane sugar
fermentation is set up. The cane sugar, however, does not ferment
directly: the enzyme in the yeast first transforms the sugar into
dextrose and levulose, and these sugars then undergo alcoholic
fermentation.
When heated to 160° cane sugar melts; if the temperature is increased to
about 215°, a partial decomposition takes place and a brown substance
known as caramel forms. This is used largely as a coloring matter.
~Milk sugar~ (C_{12}H_{22}O_{11}). This sugar is present in the milk of
all mammals. The average composition of cow's milk is as follows:
Water 87.17%
Casein (nitrogenous matter) 3.56
Butter fat 3.64
Milk sugar 4.88
Mineral matter 0.75
When _rennin_, an enzyme obtained from the stomach of calves, is added
to milk, the casein separates and is used in the manufacture of cheese.
The remaining liquid contains the milk sugar which separates on
evaporation; it resembles cane sugar in appearance but is not so sweet
or soluble. The souring of milk is due to the fact that the milk sugar
present undergoes _lactic fermentation_ in accordance with the equation
C_{12}H_{22}O_{11} + H_{2}O = 4C_{3}H_{6}O_{3}.
The lactic acid formed causes the separation of the casein, thus giving
the well-known appearance of sour milk.
~Isomeric compounds.~ It will be observed that cane sugar and milk sugar
have the same formulas. Their difference in properties is due to the
different arrangement of the atoms in the molecule. Such compounds are
said to be isomeric. Dextrose and levulose are also isomeric.
~Dextrose~ (_grape sugar, glucose_) (C_{6}H_{12}O_{6}). This sugar is
present in many fruits and is commonly called grape sugar because of its
presence in grape juice. It can be obtained by heating cane sugar with
dilute acids, as explained above; also by heating starch with dilute
acids, the change being as follows:
C_{6}H_{10}6_{5} + H_{2}O = C_{6}H_{12}O_{6}.
Pure dextrose is a white crystalline solid, readily soluble in water,
and is not so sweet as cane sugar. In the presence of yeast it undergoes
alcoholic fermentation. It is prepared from starch in large quantities,
and being less expensive than cane sugar, is used as a substitute for it
in the manufacture of jellies, jams, molasses, candy, and other sweets.
The product commonly sold under the name of _glucose_ contains about 45%
of dextrose.
~Levulose~ _(fruit sugar)_(C_{6}H_{12}O_{6}). This sugar is a white solid
which occurs along with dextrose in fruits and honey. It undergoes
alcoholic fermentation in the presence of yeast.
~Cellulose~ (C_{6}H_{10}O_{5}). This forms the basis of all woody fibers.
Cotton and linen are nearly pure cellulose. It is insoluble in water,
alcohol, and dilute acids. Sulphuric acid slowly converts it into
dextrose. Nitric acid forms nitrates similar to nitroglycerin in
composition and explosive properties. These nitrates are variously known
as nitrocellulose, pyroxylin, and gun cotton. When exploded they yield
only colorless gases; hence they are used especially in the manufacture
of smokeless gunpowder. _Collodion_ is a solution of nitrocellulose in a
mixture of alcohol and ether. _Celluloid_ is a mixture of nitrocellulose
and camphor. _Paper_ consists mainly of cellulose, the finer grades
being made from linen and cotton rags, and the cheaper grades from straw
and wood.
~Starch~ (C_{6}H_{10}O_{5}). This is by far the most abundant carbohydrate
found in nature, being present especially in seeds and tubers. In the
United States it is obtained chiefly from corn, nearly 80% of which is
starch. In Europe it is obtained principally from the potato. It
consists of minute granules and is practically insoluble in cold water.
These granules differ somewhat in appearance, according to the source of
the starch, so that it is often possible to determine from what plant
the starch was obtained. When heated with water the granules burst and
the starch partially dissolves. Dilute acids, as well as certain
enzymes, convert it into dextrose or similar sugars. When seeds
germinate the starch present is converted into soluble sugars, which are
used as food for the growing plant.
~Chemical changes in bread making.~ The average composition of wheat flour
is as follows:
Water. 13.8%
Protein (nitrogenous matter) 7.9
Fats 1.4
Starch 76.4
Mineral matter 0.5
In making bread the flour is mixed with water and yeast, and the
resulting dough set aside in a warm place for a few hours. The yeast
first converts a portion of the starch into dextrose or a similar sugar,
which then undergoes alcoholic fermentation. The carbon dioxide formed
escapes through the dough, making it light and porous. The yeast plant
thrives best at about 30°; hence the necessity for having the dough in a
warm place. If the temperature rises above 50°, the vitality of the
yeast is destroyed and fermentation ceases. In baking the bread, the
heat expels the alcohol and also expands the bubbles of carbon dioxide
caught in the dough, thus increasing its lightness.
SOME DERIVATIVES OF BENZENE
Attention has been called to the complex nature of coal tar. Among the
compounds present are the hydrocarbons, benzene, toluene, naphthalene,
and anthracene. These compounds are not only useful in themselves but
serve for the preparation of many other important compounds known under
the general name of coal-tar products.
~Nitrobenzene~ (_oil of myrbane_) (C_{6}H_{5}NO_{2}). When benzene is
treated with nitric acid a reaction takes place which is expressed by
the following equation:
C_{6}H_{6} + HNO_{3} = C_{6}H_{5}NO_{2} + H_{2}O.
The product C_{6}H_{5}NO_{2} is called nitrobenzene. It is a slightly
yellowish poisonous liquid, with a characteristic odor. Its main use is
in the manufacture of aniline.
~Aniline~ (C_{6}H_{5}NH_{2}). When nitrobenzene is heated with iron and
hydrochloric acid the hydrogen evolved by the action of the iron upon
the acid reduces the nitrobenzene in accordance with the following
equation:
C_{6}H_{5}NO_{2} + 6H = C_{6}H_{5}NH_{2} + 2H_{2}O.
The resulting compound is known as aniline, a liquid boiling at 182°.
When first prepared it is colorless, but darkens on standing. Large
quantities of it are used in the manufacture of the _aniline or coal-tar
dyes_, which include many important compounds.
~Carbolic acid~ (C_{6}H_{5}OH). This compound, sometimes known as
_phenol_, occurs in coal tar, and is also prepared from benzene. It
forms colorless crystals which are very soluble in water. It is strongly
corrosive and very poisonous.
~Naphthalene and anthracene.~ These are hydrocarbons occurring along with
benzene in coal tar. They are white solids, insoluble in water. The
well-known _moth balls_ are made of naphthalene. Large quantities of
naphthalene are used in the preparation of _indigo_, a dye formerly
obtained from the indigo plant, but now largely prepared by laboratory
methods. Similarly anthracene is used in the preparation of the dye
_alizarin_, which was formerly obtained from the madder root.
THE ALKALOIDS
This term is applied to a group of compounds found in many plants and
trees. They all contain nitrogen, and most of them are characterized by
their power to combine with acids to form salts. This property is
indicated by the name alkaloids, which signifies alkali-like. The salts
are soluble in water, and on this account are more largely used than the
free alkaloids, which are insoluble in water. Many of the alkaloids are
used in medicine, some of the more important ones being given below.
~Quinine.~ This alkaloid occurs along with a number of others in the bark
of certain trees which grow in districts in South America and also in
Java and other tropical islands. It is a white solid, and its sulphate
is used in medicine in the treatment of fevers.
~Morphine.~ When incisions are made in the unripe capsules of one of the
varieties of the poppy plant, a milky juice exudes which soon thickens.
This is removed and partially dried. The resulting substance is the
ordinary _opium_ which contains a number of alkaloids, the principal one
being morphine. This alkaloid is a white solid and is of great service
in medicine.
Among the other alkaloids may be mentioned the following: _Nicotine_, a
very poisonous liquid, the salts of which occur in the leaves of the
tobacco plant; _cocaine_, a crystalline solid present in coca leaves and
used in medicine as a local anæsthetic; _atropine_, a solid present in
the berry of the deadly nightshade, and used in the treatment of
diseases of the eye; _strychnine_, a white, intensely poisonous solid
present in the seeds of the members of the _Strychnos_ family.
INDEX
Acetaldehyde 405
Acetic acid 406
Acetone 411
Acetylene 203
series 399
Acids 106
binary 113
characteristics 106
definition 107
dibasic 159
familiar 106
monobasic 159
nomenclature 113
organic 405
preparation 141
strength 111
ternary 113
undissociated 107
Acker furnace, 279
Agate 260
Air 83
a mechanical mixture 89
carbon dioxide in 87
changes in composition 87
liquid 91
nitrogen in 87
oxygen in 85
poisonous effects of exhaled 88
properties 90
quantitative analysis of 85
regarded as an element 83
standard for density 229
water vapor in 87
Alabaster 308
Alchemists 9
Alchemy 9
Alcohol, common 402
denatured 404
ethyl 402
methyl 402
wood 402
Alcohols 401
Aldehydes 405
Alizarin 418
Alkali 107, 274
family 274
Alkaline-earth family 300
Alkaloids 418
Allotropic forms 22
Alloys 252
Alum 333
ammonium 334
ammonium chrome 384
ammonium iron 352
baking powders 335
potassium 333
potassium chrome 384
potassium iron 352
Aluminates 332
Aluminium 327
bronze 330, 359
chloride 333
family 327
hydroxide 332
metallurgy 328
occurrence 327
oxide 331
preparation 328
properties 329
silicates 335
uses 330
Amalgam 362
Amethyst 260, 331
Ammonia 123
composition 127
preparation 123
properties 124
uses 125
Ammonium 126
acid carbonate 295
carbonate 295
chloride 294
compounds 294
Ammonium hydrosulphide 296
hydroxide 126
molybdate 388
oxalate 407
sulphate 295
sulphide 295
sulphide, yellow 296
Analysis 40
Anhydride 135
carbonic 206
chromic 387
nitric 135
nitrous 135
phosphoric 243
sulphuric 153
Anhydrite 288
Aniline 417
Anion 106
Anode 99
Anthracene 418
Antimony 250
acids 251
alloys 253
chloride 252
metallic properties 252
occurrence 251
oxides 251
preparation 251
properties 251
sulphides 251
Apatite 175, 239, 311
Aqua ammonia 124
Aqua regia 185
Aqueous tension 25
Argon 80
Arsenic 246
acids 250
antidote 250
Marsh's test 248
occurrence 246
oxides 249
preparation 246
properties 247
sulphides 250
white 249
Arsenopyrites 246
Arsine 247
Asbestos 321, 336
Atmosphere 83
constituents 83
function of constituents 84
Atomic hypothesis 61
theory 59
and laws of matter 63
and radium 314
weights, 65
accurate determination 231
and general properties 167
and specific heats 233
calculation of 231
Dalton's method 223
direct determination 233
from molecular weights 230
relation to equivalent 224
standard for 66
steps in determining 224
Atoms 62
size 65
Atropine 419
Aurates 396
Avogadro's hypothesis 226
and chemical calculations 235
and molecular weights 227
Azote 78
Azurite 357
Babbitt metal 253
Bacteria 85
decomposition of organic matter by 122
nitrifying 85
Baking powders 285, 408
alum 335
soda 285
Barium 312
chloride 313
nitrate 313
oxides 312
sulphate 313
Barytes 312
Bases 107
characteristics 107
definition 108
familiar 107
nomenclature 113
organic 412
strength 113
undissociated 108
Basic lining process 346
Bauxite 332
Beer 404
Benzene 417
derivatives 417
series 399
Benzine 400
Bessemer process 345
Bismuth 253
basic salts 255
chloride 253
nitrate 253
occurrence 253
oxides 254
preparation 253
salts, hydrolysis of 254
subnitrate 256
uses 253
Bismuthyl chloride 256
Blast furnace 341
lamp 38
Bleaching powder 306
Bleaching by chlorine 181
by sulphurous acid 152
Boiler scale 320
Bone ash 311
Bone black 200
Borax 265
bead 266
Bornite 357
Boron 257, 264
acids 265
fluoride 264
hydride 264
occurrence 264
oxides 264
preparation 264
properties 264
Brass 323
Bread making 416
Bromides 190
Bromine 187
occurrence 187
oxygen compounds 190
preparation 187
properties 188
Bronze 359
aluminium 330, 359
Butter fat 410
Butyric acid 407
By-product 284
Cadmium 325
compounds 326
Cæsium 294
Calamine 321
Calcite 305
Calcium 301
carbide 203, 310
carbonate 305
chloride 306
fluoride 308
hydroxide 303
occurrence 301
oxide 302
phosphate 246, 311
preparation 302
sulphate 308
Calomel 363
Calorie 76
Caramel 414
Carbohydrates 413
Carbolic acid 417
Carbon 196
allotropic forms 196
amorphous 198
compounds 196
crystalline forms 197
cycle in nature 88
dioxide 204
and bases 206
and plant life 88
in air 87
occurrence 204
preparation 204
properties 204
solid 204
disulphide 160, 210
family 196
hydrogen compounds 201
monoxide 208
occurrence 196
oxides 203
properties 200
pure 198
retort 199
uses 200
Carbonates 207
acid 207
Carbonic acid 206
Carborundum 259
Carnallite 288
Casein 414
Cassiterite 370
Catalysis 153
Catalyzers 153
Cathode 99
Cation 106
Caustic potash 288
soda 278
Celestite 312
Celluloid 415
Cellulose 415
Cement 304
Ceramic industries 336
Cerium 377
Chalcedony 260
Chalcocite 357
Chalcopyrite 357
Chalk 305
Chamber acid 157
Changes, physical and chemical 2
Charcoal 199
Chemical affinity 12
changes 2
compounds 7
equilibrium 128
properties 3
Chemistry, definition 4
Chili saltpeter 191, 285
Chinaware 336
Chloric acid 187
Chlorides 186
Chlorine 177
bleaching action 181
chemical properties 180
family 174
historical 177
occurrence 178
oxides 187
oxygen acids 187
preparation 178
properties 179
Chloroform 401
Chloroplatinic acid 393
Chlorous acid 187
Chromates 385
Chrome alum 384
Chromic acid 388
anhydride 387
chloride 383
hydroxide 383
sulphate 384
sulphide 384
Chromite 383
Chromium 383
a base-forming element 383
an acid-forming element 385
occurrence 383
Cinnabar 363
Citric acid 408
Clay 336
Coal 199
gas 217
products 400
tar 218
Cobalt 354
compounds 354
Cocaine 419
Coke 199
Collodion 415
Colemanite 265
Combining weights 225
Combustion 17
broad sense 20
in air 19
phlogiston theory 19
products 18
spontaneous 20
supporters 213
Compounds, chemical 7
isomeric 414
of metals, preparation 265
structure of 118
Conservation of energy 4
of matter 5
Contact process 154
Converter, Bessemer 345
Copper 357
acetate 407
alloys of 359
family 356
hydroxide 360
metallurgy 357
occurrence 357
ores 357
oxide 360
properties 358
refining 358
sulphate 361
sulphide 361
uses 359
Copperas 350
Coral 305
Corrosive sublimate 363
Corundum 331
Cream of tartar 408
Crocoisite 383
Cryolite 175, 328
Crystallization 98
water of 54, 75
Crystallography 161
Crystals 161
axes of 161
systems 162
Cupric compounds 360
Cuprite 360
Cuprous compounds 360
chloride 360
oxide 360
Cyanides 210
solutions are alkaline 210
Dalton's atomic hypothesis 61
Decay 21
Decomposition of organic matter 122
Decrepitation 55
Deliquescence 55
Density of gases 230
Desiccating agents 55
Developers 367
Dewar bulb 91
Dextrose 414
Diamond 197
Dichromates 385
Dichromic acid 385
Dimorphous substances 163
Dissociation 99
and boiling point 101
and freezing point 101
equations of 112
extent of 113
Distillation 50
Dogtooth spar 306
Dolomite 319
Double decomposition 71
Drummond light 38
Dyeing 333
Dynamite 409
Earth metals 327
Efflorescence 54
Electric furnace 221
Electro-chemical industries 269
Electrode 99
Electrolysis 99
of sodium chloride 102
of sodium sulphate 103
of water 41, 102
Electrolytes 99
Electrolytic dissociation 99
Electroplating 366
Electrotyping 359
Elements, definition 8
atomic weights 232
earlier classification 165
names 11
natural groups 165
number of 9
occurrence 10
periodic division 166
physical state 10
symbols of 11
Emery 331
Energy 4
and plant life 89
chemical 5
conservation of 4
transformation of 5
Enzyme 405
Epsom salts 320
Equations 68
are quantitative 72
knowledge requisite for 69
not algebraic 74
reading of 69
Equilibrium 138
chemical 138
in solution 139
point of 138
Equivalent 224
determination of 224
elements with more than one 225
relation to atomic weight 224
Etching 177
Ether 411
Ethereal salts 409
Ethers 411
Ethylamine 412
Ethylene series 399
Eudiometer 43
Evaporation 11
Families in periodic groups 170
triads 165
Family resemblances 170
Fats 409
Fatty acid series 405
Feldspar 261, 335
Fermentation 404
acetic 406
alcoholic 404, 405
lactic 414
Ferric chloride 352
hydroxide 352
salts 351
reduction 353
sulphate 352
Ferrochromium, 383
Ferromanganese 343
Ferrosilicon 259
Ferrous carbonate 351
salts 350
oxidation of 353
sulphate 350
sulphide 350
Fertilizers 245
Filtration 6, 51
beds 52
Fire damp 202
Flames 213
appearance 214
blowpipe 216
Bunsen 214
conditions for 213
hydrogen 34
luminosity 216
oxidizing 214
oxyhydrogen 37
reactions 296
reducing 214
structure 214
Flash lights 317
Flint 260
Fluorides 177
Fluorine 175
Fluorspar 175, 308
Fluosilicic acid 259
Flux 340
Fool's gold 351
Formaldehyde 405
Formalin 405
Formic acid 406
Formulas 68
how determined 234
structural 119
Fractional distillation 51
Franklinite 321
Fuels 220
Furnace, arc 221
electric 221
resistance 221
Fusion methods 271
Galena 373
Gallium 327
Galvanized iron 323
Gas, collection of 15
coal 217
fuel 217
illuminating 217
measurement of 23
natural 219
purification of 218
water 219
Gases, table 220
Gasoline 400
German silver 323, 359
Germanium 370
Germs, effect of cold on 53
in air 84
in water 52
Glass 262
coloring of 263
etching of 177
molding of 263
nature of 263
varieties 263
Glauber's salt 281
Glazing 336
Glucose 414
Glycerin 405
nitrates of 409
Gold 393
alloys 396
chloride 396
coin 359
extraction of 394
in copper 358
mining 394
occurrence 393
properties 396
refining of 395
telluride 394
Goldschmidt method 269, 330
Gram-molecular weight 236
Granite 336
Graphite 198
Gun cotton 415
metal 359
powder 292
Gypsite 308
Gypsum 308
Halogens 174
Hard water 309
Heat of reaction 75
Helium 80, 314
Hematite 339, 349
Homologous series 398
Hydriodic acid 193
Hydrobromic acid 189
Hydrocarbons 201, 398
properties 400
series 398
substitution products 401
Hydrochloric acid 182
composition 183
oxidation of 185
preparation 182
properties 184
salts 186
Hydrocyanic acid 210
Hydrofluoric acid 176
etching by 177
salts of 177
Hydrogen 28
dioxide 56
explosive with oxygen 35
occurrence 28
preparation from acids 30
preparation from water 28
properties 32
standard for atomic weights 66
standard for molecular weights 227
sulphide 146
uses 38
Hydrolysis 254
conditions affecting 255
partial 255
Hydrosulphuric acid 146
Hydroxyl radical 112
Hypochlorous acid 187
Hypothesis 61
Avogadro's 226
Dalton's 61
Ice manufacture 125
Iceland spar 305
Indigo 418
Indium 327
Insoluble compounds 272
Iodic acid 194
Iodides 193
Iodine 190
oxygen compounds 193
preparation 191
properties 192
tincture 192
Iodoform 192, 401
Ions 100
and electrolytes 104
Iridium 393
Iron 339
alum 352
cast 343
compounds 349
cyanides 352
disulphide 351
family 338
metallurgy 339
occurrence 339
ores 339
oxides 349
pure 348
varieties 342, 347
wrought 343
Jasper 260
Kainite 288
Kaolin 261, 335
Kerosene 400
Ketones 411
Kieserite 288
Kindling temperature 17
Krypton 80
Lactic acid 408
Lampblack 200
Laughing gas 132
Law, definition 61
of Boyle 24
of Charles 23
of combining volumes 194
of conservation of energy 4
of conservation of matter 5, 59
of definite composition 59
of Dulong and Petit 233
of Gay-Lussac 194
of multiple proportion 60
of Raoult 233
periodic 169
Lead 373
acetate 375, 407
alloys 375
basic carbonate 376
carbonate 376
chloride 377
chromate 377
insoluble compounds 376
metallurgy 373
nitrate 375
occurrence 373
oxides 375
peroxide 375
properties 374
red 375
soluble salts 375
sugar of 375
sulphate 377
sulphide 377
white 376
Le Blanc soda process 282
Levulose 415
Lime 302
air-slaked 303
hypochlorite 307
kilns 303
slaked 303
Lime light 38
Limestone 305
Limewater 303
Limonite 339
Litharge 375
Lithium 294
Luminosity of flames 216
Lunar caustic 366
Magnesia 318
alba 319
usta 318
Magnesite 318
Magnesium 317
basic carbonate 319
carbonate 318
cement 318
chloride 319
family 316
hydroxide 318
oxide 318
silicates 321
sulphate 320
Magnetite 339, 349
Malachite 357
Manganates 381
Manganese 379
a base-forming element 380
an acid-forming element 381
in glass 263
occurrence 379
oxides 380
Manganic acid 381
Manganous salts 380
Marble 305
Marl 305
Marsh gas 202
Matches 242
Matte 358
Matter, classification 6
conservation 5
definition 5
kinds 9
Measurement of gases 23
Mechanical mixtures 6
Meerschaum 321, 336
Mercuric chloride 363
iodide 364
oxide 14, 362
sulphide 363
Mercurous chloride 363
Mercury 361
iodides 364
metallurgy 361
occurrence 361
oxides 362
uses 362
Metaboric acid 265
Metallurgy 268
Metals 165, 267
action on salts 271
definition 267
extraction 268
occurrence 267
preparation of compounds 269
reduction from ores 268
Metaphosphoric acid 245
Metarsenic acid 250
Metasilicic acid 261
Metastannic acid 371
Methane 202, 399
Methylamine 412
Mexican onyx 305
Mica 261, 336
Microcosmic salt 244
Milk 414
Minerals 267
Minium 375
Mixed salts 244
Molasses 413
Molecular weights 226
boiling-point method 233
compared with oxygen 228
determination 226
freezing-point method 233
oxygen standard 227
of elements 232
vapor-density method 229
Molecule 62
Molybdenum 388
Molybdic acid 388
Monazite sand 377
Mordants 333
Morphine 418
Mortar 304
Moth balls 418
Muriatic acid 182
Naphthalene 418
Naphthas 400
Nascent state 182
Natural gas 219
sciences 1
Neon 80
Neutralization 108
a definite act 109
definition 109
heat of 109
partial 111
Niagara Falls 269, 329
Nickel 354
coin 359
compounds 354
plating 354
Nicotine 419
Nitrates 131
Nitric acid, 128
action on metals 130
decomposition 129
oxidizing action 130
preparation 128, 140
properties 129
salts 131
Nitric oxide 133
Nitrites 132
Nitrobenzene 417
Nitrocellulose 415
Nitrogen 78
compounds 122
in air 87
occurrence 78, 122
oxides 132
preparation 78
properties 80
Nitroglycerin 409
Nitrosulphuric acid 155
Nitrous acid 132
oxide 132
Non-metals 165
Oil of myrbane 417
of vitriol 154
Oleic acid 408
Olein 409
Oleomargarine 410
Onyx 260
Opal 260
Open-hearth process 346
Opium 418
Ores 267
Organic bases 412
chemistry 201, 397
matter, decomposition 122
Orpiment 246
Orthoarsenic acid 250
Orthophosphates 244
Orthophosphoric acid 244
Orthosilicic acid 261
Osmic acid 393
Osmium 393
tetroxide 393
Oxalic acid 407
Oxidation 17, 353
definition 18
Oxidizing agent 37
Oxygen 13
and ozone 22
commercial preparation 16
history 13
importance 21
in air estimation, 85
in air function, 84
occurrence 13
preparation 13
properties 16
standard for atomic weights 66
two atoms in molecule 227
Oxyhydrogen blowpipe 37
Ozone 21, 137
Palladium 390
Palmitic acid 407
Palmitin 409
Paraffin 400
Paris green 250
Parkes's method for silver 364
Pearls 305
Perchloric acid 187
Periodic acid 194
Periodic division 166
groups 167
law 169
law, imperfections 172
law, value 171
table 168
table, arrangement 166
Permanent hardness 310
Permanganates 381
Permanganic acid 381
Peroxides 278
Petroleum 399
Pewter 372
Phenol 417
Philosopher's stone 9
Phlogiston 19
Phosphates 245
Phosphine 242
Phosphonium compounds 243
Phosphoric acid 244
Phosphorite 239
Phosphorous acid 244
Phosphorus 239
acids 243
family 238
hydrogen compounds 242
occurrence 239
oxides 243
preparation 239
properties 240
red 241
yellow 240
Photography 367
Physical changes 2
properties 3
properties and periodic groups 171
state 3
Physics 1, 4
Pitchblende 314
Plaster of Paris 308
Platinic chloride 393
Platinized asbestos 391
Platinous chloride 393
Platinum 391
a catalytic agent 152, 392
Pneumatic trough 16
Polyboric acid 265
Polyhalite 288
Polysilicic acids 261
Porcelain 336
Portland cement 304
Potash 293
Potassium 287
acid carbonate 294
acid sulphate 294
acid sulphite 294
alum, aluminium 334
alum, chrome 384
alum, iron 352
and plant life 287
aurate 396
bromide 290
carbonate 293
chlorate 291
chloride 290
chromate 385
cyanide 293
dichromate 386
ferricyanide 352
ferrocyanide 352
hydroxide 288
hydroxide, action of halogens 289
hypochlorite 289
iodide 290
manganate 381
nitrate 291
occurrence 287
permanganate 381
preparation 288
sulphate 294
Precipitated chalk 306
Precipitation 140
Properties, chemical 3
physical 3
Prussic acid 210
Puddling 343
furnace 344
Pyridine 412
Pyrites 351
Pyrolusite 380
Pyrophosphoric acid 245
Quantitative equations 72
Quartz 260
Quicklime 302
Quinine 418
Quinoline 412
Radical 112
Radium 313
Reaction, classes 70
addition 70
completed 139
heat of 75
of decomposition 70
of double decomposition 71
of substitution 70
reversible 137
steps in 131
Realgar 246
Red lead 375
phosphorus 241
Reducing agent 37
Reduction 36, 354
Rennin 414
Resemblances, family 170
Respiration 87
Rhodium 390
Rochelle salts 408
Rouge 349
Rubidium 294
Ruby 331
Ruthenium 390
Rutile 264
Safety lamp 202
Sal ammoniac 294
soda 282
Salt 280
Saltpeter 291
Chili 285
Salts, 109
acid, 112
Salts basic 111
binary 114
characteristics 109
definition 109
insoluble 272
mixed 244
nomenclature 113
normal 112
preparation by precipitation 270
Sand 260
Sandstone 260
Saponification 410
Sapphire 331
Satinspar 308
Scale 320
Schönite 288
Selenite 308
Selenium 161
Serpentine 320, 336
Shot 247, 375
Siderite 339
Silica 260
Silicates 261
Silicic acids 261
Silicides 259
Silicon 258
acids 261
dioxide 260
fluoride 258
hydride 258
Silver 364
amalgamation process 364
bromide 367
chloride 367
coin 359
German 359
in copper ores 358
iodide 367
metallurgy 364
nitrate 366
oxide 366
parting of 365
refining 365
sulphide 366
Slag 340
Smalt 355
Smithsonite 321
Smokeless powder 293
Soaps 410
Soda ash 284
Soda lime 202
Sodium 276
acetate 407
bicarbonate 285
carbonate 282
carbonate, historical 284
chloride 280
chromates 386
hydrogen carbonate 285
hydroxide 278
hyposulphite 282
iodate 191
nitrate 285
occurrence 276
peroxide 277
phosphates 286
preparation 276
properties 277
sulphate 281
sulphite 281
tetraborate 287
thiosulphate 282
Solder 372, 375
Solubility of gases 95
of solids 96
Solution 94
and chemical action 53
boiling point 98
classes 94
distribution of solids in 98
electrolysis of 99
freezing point 99
of gases in liquids 94
of solids in liquids 96
properties 98
saturated 97
supersaturated 98
Solvay soda process 283
Sombrerite 239
Spectroscope 296
Sphalerite 325
Spiegel iron 343
Spinel 332
Spontaneous combustion 20
Stalactites 305
Stalagmites 305
Standard conditions 23
Stannates 372
Stannic acid 372
chloride 372
oxide 372
Stannous chloride 372
Starch 415
Stassfurt salts 287
Stearic acid 407
Stearin 409
Steel 345
alloys 348
properties 347
tempering of 348
tool 347
Stibine 251
Stibnite 250
Stoneware 336
Strontianite 312
Strontium 312
hydroxide 312
nitrate 312
Structural formulas 119
Structure of compounds 119
Strychnine 419
Substitution 70
Sugars 412
cane 412
fruit 415
grape 414
milk 414
Sulphates 159
Sulphides 148
Sulphites 152
action of acids on 150
Sulphur 143
allotropic forms 144
chemical properties 145
comparison with oxygen 161
dioxide 149
preparation 149
properties 150
extraction 143
flowers of 143
occurrence 143
oxides 149
physical properties 144
trioxide 152
uses 146
varieties 144
Sulphuric acid 154
action as an acid 157
action on metals 157
action on organic matter 158
action on salts 158
action on water 158
fuming 155
manufacture 154
oxidizing action 157
plant 156
properties 157
salts 159
Sulphuric anhydride 153
Sulphurous acid 151
Superphosphate of lime 246
Sylvine 288
Symbols 11
Synthesis 40
Table, alkali metals 274
alkaline-earth metals 300
alloys of copper 359
aqueous tension Appendix B
atomic weights Appendix A
chlorine family 174
composition of earth's crust 10
composition of fuel gases 220
constants of elements Appendix B
copper family 356
elements Appendix A
gold and platinum metals 390
hydrocarbons 399
magnesium family 316
manganese and chromium 379
periodic arrangement 168
phosphorus family 238
silicon family 257
solubility of gases in water 95
solubility of salts 96
solubility of salts at different temperatures 97
tin and lead 370
weights of gases Appendix B
Talc 321, 336
Tartar emetic 408
Tartaric acid 408
Tellurium 161
Temporary hardness 309
Ternary acids 113
salts 114
Tetraboric acid 265
Thallium 327
Theory, atomic 61
definition 64
value of 64
Thermite 331
Thio compounds 282
Thiosulphates 159
Thiosulphuric acid 159
Thorium 377
Tin 370
block 371
compounds 372
crystals 372
family 370
foil 371
metallurgy 370
plate 371
properties 371
uses 371
Titanium 257, 264
Topaz 331
Triad families 166
Tungsten 388
Type metal 253, 375
Uranium 388
Valence 116
a numerical property 116
and combining ratios 118
and equations 120
and formulas 120
and periodic groups 162
and structure 118
definition 116
indirectly determined 117
measure of 117
variable 117
Vaseline 400
Venetian red 349
Verdigris 407
Vermilion 363
Vinegar 406
Vitriol, blue 361
green 350
oil of 154
white 324
Volume and aqueous tension 25
and pressure 24
and temperature 23
of combining gases 194
Water 40
a compound 40
and disease 49
catalytic action of 154
chalybeate 351
chemical properties 53
composition 47
composition by volume 44
composition by weight 47
dissociation of 210
distillation of 50
electrolysis of 41, 103
filtration of 51
gas 219
hard 309
historical 40
impurities in 48
in air 87
mineral 49
occurrence 48
of crystallization 54, 75
physical properties 53
purification of 50
qualitative analysis 41
quantitative analysis 42
river 49
sanitary analysis 50
self-purification 53
softening of 310
standard substance 55
synthesis 43
uses of 55
Weights, atomic 65
Welsbach mantles 219, 377
Whisky 404
Wine 404
Witherite 312
Wood alcohol 402
distillation 402
Wood's metal 254
Xenon 80
Yeast 403
Zinc 321
alloys of 323
blende 321
chloride 325
flowers of 322
metallurgy 321
occurrence 321
oxide 324
sulphate 324
sulphide 325
white 324
Zymase, 403
ANNOUNCEMENTS
AN ELEMENTARY STUDY OF CHEMISTRY
By WILLIAM McPHERSON, Professor of Chemistry in Ohio State University,
and WILLIAM E. HENDERSON, Associate Professor of Chemistry in Ohio State
University.
12mo. Cloth. 434 pages. Illustrated. List price, $1.25; mailing price,
$1.40
This book is the outgrowth of many years of experience in the teaching
of elementary chemistry. In its preparation the authors have steadfastly
kept in mind the limitations of the student to whom chemistry is a new
science. They have endeavored to present the subject in a clear,
well-graded way, passing in a natural and logical manner from principles
which are readily understood to those which are more difficult to grasp.
The language is simple and as free as possible from unusual and
technical phrases. Those which are unavoidable are carefully defined.
The outline is made very plain, and the paragraphing is designed to be
of real assistance to the student in his reading.
The book is in no way radical, either in the subject-matter selected or
in the method of treatment. At the same time it is in thorough harmony
with the most recent developments in chemistry, both in respect to
theory and discovery. Great care has been taken in the theoretical
portions to make the treatment simple and well within the reach of the
ability of an elementary student. The most recent discoveries have been
touched upon where they come within the scope of an elementary text.
Especial attention has been given to the practical applications of
chemistry, and to the description of the manufacturing processes in use
at the present time.
EXERCISES IN CHEMISTRY. By WILLIAM McPHERSON and WILLIAM E. HENDERSON.
(_In press._)
GINN & COMPANY PUBLISHERS
A FIRST COURSE IN PHYSICS
By ROBERT A. MILLIKAN, Associate Professor of Physics, and HENRY G.
GALE, Assistant Professor of Physics in The University of Chicago
12mo, cloth, 488 pages, illustrated, $1.25
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_FOR SECONDARY SCHOOLS_
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This one-year course in physics has grown out of the experience of the
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The University of Chicago, and in dealing with the physics instruction
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The book is a simple, objective presentation of the subject as opposed
to a formal and mathematical one. It is intended for the third-year
high-school pupils and is therefore adapted in style and method of
treatment to the needs of students between the ages of fifteen and
eighteen. It especially emphasizes the historical and practical aspects
of the subject and connects the study very intimately with facts of
daily observation and experience.
The authors have made a careful distinction between the class of
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are grouped into a Laboratory Manual which is designed for use in
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All the experiments included in the work have been carefully chosen with
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GINN AND COMPANY PUBLISHERS
APPENDIX A
LIST OF THE ELEMENTS, THEIR SYMBOLS, AND ATOMIC WEIGHTS
The more important elements are marked with an asterisk
O = 16
*Antimony Sb 120.2
*Argon A 39.9
*Arsenic As 75.0
*Barium Ba 137.4
Beryllium Be 9.1
*Bismuth Bi 208.5
*Boron B 11.0
*Bromine Br 79.96
*Cadmium Cd 112.4
Cæsium Cs 132.9
*Calcium Ca 40.1
*Carbon C 12.00
Cerium Ce 140.25
*Chlorine Cl 35.45
*Chromium Cr 52.1
*Cobalt Co 59.0
Columbium Cb 94.0
*Copper Cu 63.6
Erbium Er 166.0
*Fluorine F 19.0
Gadolinium Gd 156.0
Gallium Ga 70.0
Germanium Ge 72.5
*Gold Au 197.2
Helium He 4.0
*Hydrogen H 1.008
Indium In 115.0
*Iodine I 126.97
Iridium Ir 193.0
*Iron Fe 55.9
Krypton Kr 81.8
Lanthanum La 138.9
*Lead Pb 206.9
Lithium Li 7.03
*Magnesium Mg 24.36
*Manganese Mn 55.0
*Mercury Hg 200.0
Molybdenum Mo 96.0
Neodymium Nd 143.6
Neon Ne 20.0
*Nickel Ni 58.7
*Nitrogen N 14.04
Osmium Os 191.0
*Oxygen O 16.00
Palladium Pd 106.5
*Phosphorus P 31.0
*Platinum Pt 194.8
*Potassium K 39.15
Praseodymium Pr 140.5
Radium Ra 225.0
Rhodium Rh 103.0
Rubidium Rb 85.5
Ruthenium Ru 101.7
Samarium Sm 150.3
Scandium Sc 44.1
Selenium Se 79.2
*Silicon Si 28.4
*Silver Ag 107.93
*Sodium Na 23.05
*Strontium Sr 87.6
*Sulphur S 32.06
Tantalum Ta 183.0
Tellurium Te 127.6
Terbium Tb 160.0
Thallium Tl 204.1
Thorium Th 232.5
Thulium Tm 171.0
*Tin Sn 119.0
Titanium Ti 48.1
Tungsten W 184.0
Uranium U 238.5
Vanadium V 51.2
Xenon Xe 128.0
Ytterbium Yb 173.0
Yttrium Yt 89.0
*Zinc Zn 65.4
Zirconium Zr 90.6
APPENDIX B
Tension of Aqueous Vapor expressed in Millimeters of Mercury
TEMPERATURE PRESSURE
16 13.5
17 14.4
18 15.3
19 16.3
20 17.4
21 18.5
22 19.6
23 20.9
24 22.2
25 23.5
Weight of 1 Liter of Various Gases measured under Standard Conditions
Acetylene 1.1614
Air 1.2923
Ammonia 0.7617
Carbon dioxide 1.9641
Carbon monoxide 1.2499
Chlorine 3.1650
Hydrocyanic acid 1.2036
Hydrochloric acid 1.6275
Hydrogen 0.08984
Hydrosulphuric acid 1.5211
Methane 0.7157
Nitric oxide 1.3410
Nitrogen 1.2501
Nitrous oxide 1.9677
Oxygen 1.4285
Sulphur dioxide 2.8596
Densities and Melting Points of Some Common Elements
DENSITY MELTING POINT
Aluminium 2.68 640
Antimony 6.70 432
Arsenic 5.73 --
Barium 3.75 --
Bismuth 9.80 270
Boron 2.45 --
Cadmium 8.67 320
Cæsium 1.88 26.5
Calcium 1.54 --
Carbon, Diamond 3.50 --
" Graphite 2.15 --
" Charcoal 1.80 --
Chromium 7.30 3000
Cobalt 8.55 1800
Copper 8.89 1084
Gold 19.30 1064
Iridium 22.42 1950
Iron 7.93 1800
Lead 11.38 327
Lithium 0.59 186
Magnesium 1.75 750
Manganese 8.01 1900
Mercury 13.596 -39.5
Nickel 8.9 1600
Osmium 22.47 --
Palladium 11.80 1500
Phosphorus 1.80 45
Platinum 21.50 1779
Potassium 0.87 62.5
Rhodium 12.10 --
Rubidium 1.52 38.5
Ruthenium 12.26 --
Silicon 2.35 --
Silver 10.5 960
Sodium 0.97 97.6
Strontium 2.50 --
Sulphur 2.00 114.8
Tin 7.35 235
Titanium 3.50 --
Zinc 7.00 420