Chapter II: The Elementary Substances

On the following page is a list of the sixty-six elementary substances now generally recognized as such. Their respective symbols and their atomic weights, both in exact and approximate numbers, are also given.

These substances, then, nearly seventy in number, are those from which are made up all material things now known to man. While it is not necessary for any one to retain such a list in memory, every person who desires any considerable knowledge of chemistry should be acquainted with each name and the symbol attached to it, and should know something of the natural sources and the properties of the substances designated.

Six Suggestions Conveyed by this Table.

A careful and intelligent reading of the list affords several important suggestions. The following are some of them:—

_First. The elements are not very numerous._ They are in fact very few, as compared with the countless number of substances they may form by their proper combinations.

_Second. They are however sufficiently numerous to produce the many substances recognized in nature._ For, consider how human language may have many words and yet all these may be spelled out by combinations of few letters. Some English dictionaries register over a hundred thousand words, yet these are all made by the combinations of less than thirty letters. Now it is easy to comprehend how the few letters of an alphabet may be even still further combined in various ways so as to produce additional words almost without limit: in a similar manner it may be easily imagined that the sixty-five elementary substances have ample capabilities for giving rise not only to the compounds now known, but to yet more and more, almost without limit. It is true that the chemist discovers that some of the chemical elements appear to have a limited power of union, but in others he finds an apparently unbounded capacity to form new arrangements and combinations.

-------------------------------------------------------------------
The Chemist’s Elementary Substances.
===========+==================+================+===============
Name | | Exact | Approximate
of Element.| Atomic Symbol. | Atomic | Atomic Weight.
| | Weight. |
-----------+------------------+----------------+----------------
Aluminum | Al | 27.0090 | 27.
Antimony | Sb (Stibium) | 119.9550 | 120.
Arsenic | As | 74.9180 | 74.9
Barium | Ba | 136.7630 | 136.8
Bismuth | Bi | 207.5230 | 207.5
Boron | B | 10.9410 | 10.9
Bromine | Br | 79.7680 | 79.8
Cadmium | Cd | 111.8350 | 111.8
Caesium | Cs | 132.5830 | 132.6
Calcium | Ca | 39.9900 | 40.
Carbon | C | 11.9736 | 12.
Cerium | Ce | 140.4240 | 140.4
Chlorine | Cl | 35.3700 | 35.4
Chromium | Cr | 52.0090 | 52.
Cobalt | Co | 58.8870 | 58.9
Copper | Cu (Cuprum) | 63.1730 | 63.2
Didymium | D | 144.5730 | 144.6
Erbium | E | 165.8910 | 165.9
Fluorine | Fl | 18.9840 | 19.
Gallium | Ga | 68.8540 | 68.9
Glucinum | G or Be | |
| (Beryllium) | 9.0850 | 9.1
Gold | Au (Aurum) | 196.1550 | 196.2
Hydrogen | H | 1.0000 | 1.
Indium | In | 113.3980 | 113.4
Iodine | I | 126.5570 | 126.6
Iridium | Ir | 192.6510 | 192.7
Iron | Fe (Ferrum) | 55.9130 | 55.9
Lanthanum | La | 135.5260 | 138.5
Lead | Pb (Plumbum) | 206.4710 | 206.5
Lithium | Li | 7.0073 | 7.
Magnesium | Mg | 23.9590 | 24.
Manganese | Mn | 53.9060 | 53.9
Mercury | Hg (Hydrargyrum)| 199.7120 | 199.7
Molybdenum | Mo | 95.5270 | 95.5
Nickel | Ni | 57.9280 | 57.9
Niobium | Nb | 93.8120 | 93.8
Nitrogen | N | 14.0210 | 14.
Osmium | Os | 198.4940 | 198.5
Oxygen | O | 15.9633 | 16.
Palladium | Pd | 105.7370 | 105.7
Phosphorus | P | 30.9580 | 31.
Platinum | Pt | 194.4150 | 194.4
Potassium | K (Kalium) | 39.0190 | 39.
Rhodium | Rh | 104.0550 | 104.1
Rubidium | Rb | 85.2510 | 85.3
Ruthenium | Ru | 104.2170 | 104.2
Scandium | Sc | 43.9800 | 44.
Selenium | Se | 78.7970 | 78.8
Silicon | Si | 28.1950 | 28.2
Silver | Ag (Argentum) | 107.6750 | 107.7
Sodium | Na (Natrium) | 22.9980 | 23.
Strontium | Sr | 87.3740 | 87.4
Sulphur | S | 31.9840 | 32.
Tantalum | Ta | 182.1440 | 182.1
Tellurium | Te | 127.9600 | 128.
Thallium | Tl | 203.7150 | 203.7
Thorium | Th | 233.4140 | 233.4
Tin | Sn (Stannum) | 117.6980 | 117.7
Titanium | Ti | 47.9997 | 48.
Tungsten | W (Wolframium) | 183.6100 | 183.6
Uranium | U | 238.4820 | 238.5
Vanadium | Va | 51.2560 | 51.3
Ytterbium | Yb | 172.7610 | 172.8
Yttrium | Y | 89.8160 | 89.8
Zinc | Zn | 64.9045 | 64.9
Zirconium | Zr | 89.3670 | 89.4
-----------+------------------+----------------+-------------------

_Third. The elements are mostly uncommon._ Only about one-sixth of them possess names that are familiar to ordinary readers. Thus carbon, copper, gold, iron, lead, mercury, nickel, silver, sulphur, tin, zinc, are almost the only ones in the list that can be said to suggest familiar things. Indeed some members of this list exist in the earth in extremely small quantities; but man by his ingenuity and industry has gathered up even these and brought them near to the hand of every civilized being. Thus gold exists in the earth—so far as man has access to the earth—in only very minute amounts; yet gold has a multitude of common uses beside its employment in coinage. Various forms of decorative art, like gilded lettering on books, afford familiar examples. So also mercury, which in the ordinary thermometer is very familiar to every one, exists in the earth in but minute amounts.

When the chemist examines still more narrowly the composition of the terrestrial globe, he discovers an inequality yet more extraordinary than that hinted at. Thus it appears that probably one-half of our entire planet consists of a single substance (that is, oxygen) and that one-quarter of it consists of another single substance (that is, silicon). Since an amount equal to three-quarters of the earth’s matter, by weight, is made up of but two elements, the remaining ones must necessarily exist in much smaller proportions.

The following table, given by Roscoe and Schorlemmer, shows the average composition of the earth’s crust—so far as it is accessible to human investigation by means at present known:

Percentage Composition of the Earth’s Solid Crust (by Weight).

Oxygen, 44.0 to 48.7 per cent.
Silicon, 22.8 36.2 ”
Aluminum, 9.9 6.1 ”
Iron, 9.9 2.4 ”
Calcium, 6.6 0.9 ”
Magnesium, 2.7 0.1 ”
Sodium, 2.4 2.5 ”
Potassium, 1.7 3.1 ”
————— —————
100.0 100.0

According to this table, the sum total of the amounts of _all the elements not mentioned_ may be estimated as less than one-tenth of one per cent. of the whole. This statement is rendered all the more striking when it is considered that in this minute fractional part must be included all coal and all the useful metals, except iron.

Another authority[1] declares that it is probable that an amount equal to ninety-nine one-hundredths of the entire weight of the solid, liquid and gaseous matter of our globe, is made up of only thirteen elementary substances. The elements referred to and their relative proportions are approximately represented in the diagram following:

[1] Professor J. P. Cooke.

Diagram of the Composition of our Globe (by Weight.)

+---------------------+---------------------+------------+
| | SULPHUR, HYDROGEN, | |
| | CHLORINE, NITROGEN, | 53 OTHERS |
| +---------------------+------------+
| | POTASSIUM, SODIUM, |
| | IRON, CARBON, |
| SILICON, ¼ +----------------------------------+
| | ALUMINUM, } |
| | MAGNESIUM, } ⅙ |
| | CALCIUM, } |
+---------------------+----------------------------------+
| |
| |
| |
| OXYGEN, ½ |
| |
| |
| |
+--------------------------------------------------------+

_Fourth. Most of the elements are metals._ This may not appear to the ordinary reader until he is informed that terminations in _um_, as in case of aluminum, barium, cadmium, calcium and others are intended to suggest that the substances so designated are metals. Most of the other elements having names not terminating in _um_ are called non-metals.

_Fifth. Each chemical element has an atomic symbol_, an abridgement, in some form, of its name.

_Sixth. Each chemical element has an atomic weight._ As the atomic weight of hydrogen is 1, without any fraction, it is easily understood that the weight of one atom of hydrogen is taken as the unit of the system. An inspection of the numbers given shows that in many cases the atoms weigh amounts that are very nearly exact multiples of the weight of an atom of hydrogen.

READING REFERENCES.

Atomic Weights, Calculations of

=Becker=, George F.—Atomic Weight Determinations: a digest of
the investigations published since 1814. (Published as Part IV
of the _Constants of Nature_, in Smithsonian Miscellaneous
Collections, No. 358.) 1880.

=Clarke=, Frank W.—A Recalculation of the Atomic Weights.
(Published as Part V of the _Constants of Nature_,
in Smithsonian Miscellaneous Collections, No. 441.) 1882.

———— Am. Chem. Jour. iii, 263. (1881.)

Atomic Weights, Periodicity of
=Meyer=, Lothar.—Chem. News, xli, 203.

Atomic Weights, Mendelejeff’s Law of
=Am.= Chem. Jour.—iii, 455.
=Cooke=, J. P.—Chem. Philosophy, p. 265.
=Wurtz=, Ad.—Atomic Theory, p. 154.

Atomic Weights, Arithmetical Relations of
=Hodges=, M. D. C.—Silliman’s Journal, 3d Ser. x, 277.
=Newlands=, J. A. R.—Chem. News, xlix, 198.

Atomic Weight of Oxygen.
=Odling=, W.—Jour. of Chem. Soc. of London, xi, 107.

Atomic Weight of Thallium.
=Cookes=, Wm.—Chem. News, xxix, 14, 29, 39, 55, 65, 75, 85,
97, 105, 115, 126, 137, 147, 157.

Atomic Weights, Prout’s Hypothesis of
=Cooke=, J. P.—Chemical Philosophy, 270.
=Clarke=, F. W.—Am. Chem. Journal, iii, 272. (1881.)
=Gerber=.—Silliman’s Journal, 3d Ser. xxvi, 236.

Atoms, Absolute Weight of
=Annaheim=, J.—Jour. of Chem. Soc. of London, xxxi, 31.

Elements, Defunct
=Bolton=, H. C.—American Chemist, i, 1.

Elements, Suggestions that Elements are Compound.
=Lockyer=, J. N.—Nature, Jan’y 2 and 9, also Nov. 6, 1879.
=Hastings=, C. S.—Criticism of above. Am. Chem. Jour., i, 15.