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1:06 sp. gr.
in equilibrium with water; if the acid is stronger, e.g. 1.02, the water
the same strength as that whose rate of filtration is to be determined. hi This seems at variance with the supposition that endosmose is due to dif
ference of adhesive power. A solution of 11 parts of tartaric acid in 100
as the temperature is lowered. A solution of 11 parts of citric acid in - 1:1
100 parts of water (sp. gr. 1.05) equilibrates with water just like a solu-
A solution of common salt of 1.085 sp. gr. goes over to a
aj saturated solution of a more soluble salt such as acetate of potash. ed Magnus, Pogg. 10, 160.) Endosmose proceeds from water to solutions 11
all kinds of salts, increasing in force with the strength of the solution;
is strongest with chloride of copper; then follow green and blue vitriol; til den common salt and sal-ammoniac; it is weak with chloride of iron and olphocyanide of potassium: with protochloride of tin, nitrate of silver, illud chloride of gold, which are decomposed by the bladder, no endosmose i observable. (N. Fischer, Pogg. 11, 126.) If the outer vessel contains
solution of sulphate of copper, the inner one water having a piece of
e bladder, while copper is deposited on the outer surface of the bladder,
A bladder tied over a glass filled with alcohol, swells up under water to such an extent, that when the bladder is pricked with a needle, the alcohol spirts out in a long stream. (Parrot, Pogg. 10, 166.) In this
experiment a little alcohol also passes into the water. (Magnus.) It follows, therefore, that alcohol and water exhibit contrary actions towards bladder and caoutchouc, because alcohol adheres more strongly to caoutchoue, water to bladder; water containing sulphuretted hydrogen penetrates into alcohol even more quickly than pure water. (Mitchell.) --For similar experiments by Sömmering see Alcohol.--Water passes to ether in the same manner as to alcohol. (Dutrochet.) Endosmose is directed from water to solutions of glue, gum, sugar, and white of egg; and when these liquids have the same density, 1.07, the rise of the liquid is measured in the case of glue by 3, of gum by 5, of sugar by 11, and of white of egg by 12: the last exhibits, therefore, the strongest endosmose. A solution of 1 part of gum in 16 of water passes over to a solution of 1 part of sugar in 16 or even 32 of water, although the former solution is much more viscous than the latter. If 1 part of oxalic acid is mixed with the solution of 1 of sugar in 16 of water, the endosmose is from the sugar solution to the pure water: when 2 parts of sugar and 1 of oxalic acid are dissolved in 16 of water the solution remains in equilibrium with pure water, portions of sugar and oxalic acid passing however into the water. A solution of sugar rises 3 times as high with solution of oxalio acid as with pure water in the same time; it acts in the same manner towards solutions of tartaric and citric acids. (Dutrochet.)
d. Stem of the Allium Porrum (leek). Endosmose from water to sulphuric acid of 1.0274 sp. gr. to solution of sulphuretted hydrogen, oxalic acid and tartaric acid of various degrees of concentration and at various temperatures; in the contrary direction, therefore, to that with bladder. (Dutrochet, Ann. Ch. Phys. 35, 393; 37, 191; 49, 411; 51, 159; extr. in Pogg. 138; 12, 617; 28, 359; also Ann. Chim. Ph. 60, 337.)
5. Adhesion between Solids. 1. Fine dust adheres to vertical and inverted horizontal surfaces.
2. Two heterogeneous bodies with very finely polished surfaces adhere together with a certain force. Comp. Prechtl. (Pogg. 15, 223.)
3. This kind of adhesion is most powerfully manifested when we the bodies is first brought to the liquid state (by which it acquires power of adapting itself perfectly to the surface of the other), and after wards solidified. This is the principle of glueing, pasting, soldering, si vering of mirrors, the use of mortars, cements, &c.
- Premiere - Truisiell
- Esaide Schnanbert.
5,57. raten. Reni
Chin. 89 Dalton. N
rol. Ma 1812. 1
Am. Thomsen 13, 134 a
THEORY OF AFFINITY IN GENERAL.
GEOFFROY l'ainé. Des différents Rapports observés en Chimie entre diffé
rentes Substances. Mém, de l'Acad. des Sc. de Paris, 1718, 202;
wandtschaft. Erfurt, 1780.
Crell. 5 vol. Berl, u. Stettin, 1783–1801.
Méthodique, Chimie, Pharmacie et Metallurgie. Paris, 1786, 1, 535.
Neuere Gegenstände der Chemie. Breslau. Heft 7–9. 1796
Première et seconde suite des Recherches.
Essai de Statique Chimique. 2 Bände. Paris, 1803.
On Chemical Combination and Decomposition. J. pr. Chem. rsten. Revision der Chemischen Affinitätslehre. Leipzig, 1803.
Relation of Composition to Form. Schw. 65, 320 and 394.
On the Precipitation of Metallic Oxides one by another.
vol. Manchester, 1808: translated into German by Wolff. Berlin,
Ann. Phil. 3, 174; also Schw. 14, 462. Thomson, on Stoichiometry. Ann. Phil. 2, 32, 109, 167 and 293; 3, 134 and 375; 4, 11 and 83; 5, 184; 7, 343; 12, 338 and 436;
16, 161 and 327; 17, 3; 18, 120. Further, Records of Gen. Sc.
1836, No. 15, 179; also J. pr. Chem. 8, 359.
Electro-chemistry. Gilb. 37, 249 and 415; 38, 161; 40, 162 and
L'eber die chemischen Proportionen und die chemischen Wirkungen
Lehrbuch der Chemie. Ausg. 3. Dresd. und Leipz. 1833. 1, 3;
Weights of Gases. Ann. Phil. 6, 321.
On the Densities of Elastic Fluids considered in relation to their
Stoichiometrical values. Schw. 22, 137.
Sch, 37, 387. N, Tr. 7, 2, 40 B. 9, 2, 3.
Phys. 4, 72; also Schw. 19, 462.-Further, Ann. Chim. Phys. 7,
399; also Schu. 24, 110.-Further, Ann. Chim. Phys. 8, 5 and 14, 326.
Chim. Phys. 14, 172; 19, 350; 24, 264 and 355.--- Further, Pogg.
On the relation between the Specific Gravity and Atomic Weight
On Action by Contact. Pogg. 31, 281.
Lehrbuch der Chemie. Aufl. 2, 1834. Berlin. 1,368, bis E. Turner on Chemical Equivalents. Phil
. Trans. 1829, 291; 1833, 5-
Mathematical Principles of the Theory of Affinity. Ann. P!
Mag. Ann. 1, 411.
22, 322. Fechner, on the Relation of the Law of Gravitation to the Doctrindiniform
Affinity. Kastn. Arch. 15, 257. N. Fuchs, on Amorphism. Schw. 67, 418. Pogg. 34, 577. I. pr. product
7, 344. J. Dumas, on the Atomic Theory. Ann. Chim. Phys. 33, 337; also Po
9, 293 and 416; also Schw. 49, 336 and 50, 215.
J. Dumas, on Isomerism. Ann. Chim. Phys. 47,324; also Pogg. 26, 315.
Spec. Gr. of Vapours. Ann. Chim. Phys. 50, 170.
Leçons sur la Philosophie Chimique. Paris.
into German by Otto. Braunschweig, 1840. J. Persoz. Introduction à l'Etude de la Chimie Moléculaire. Paris et
Strasbourg, 1839. Frankenheim, on Isomerism. J. pr. Chem. 16, 1. H. Kopp, on the Relation between the Atomic Weights and Spec. Gr. of
Liquid and Solid Compounds. Pogg. 47, 133; 52, 243 and 262;
also Ann. Pharm. 36, 1. Ammermüller, on the same subject. Pogg. 49, 341. H. Schroeder, on the same subject. Pogg. 50, 552; 52, 269 and 282. Biot, on Atomic Chemistry. J. pr. Ch. 22, 321. L. Gmelin. Artikel-Verwandtschaft in Gehler's Physikalischen Wörter
buch. Ausg. 2, b. 9, s. 1857.
Synonymes: Chemical Attraction, Chemical Force, Elective Attraction,
Elective Affinity, Chemische Kraft, Verwandtschaft, Wahlverwandtschaft,
History. Chemical combination was in early times attributed to the general principle of Hippocrates that like assorts with like: hence the word Affinity (Verwandtschaft) which seems to have been first employed by Barchhusen. Becher assumed, in accordance with this dogma, that when two bodies are capable of combining they must contain a common principle. Others, among whom was Lemery, supposed that solvents are furnished with a number of sharp points by means of which they are more or less adapted to insinuate themselves into the pores of solid bodies and combine with them. According to Stahl's theory, chemical combination proceeds from the intimate approximation of the parts of the combining bodies but not exactly in the manner of a wedge. Newton was the first
ho referred chemical combination to the principle of universal attraction, (hough he at the same time partly assumed that this attraction between fultimate particles is not exactly the same as that which acts between the great bodies of the universe. Geoffroy the elder, in 1718, drew up the
irst Table of Affinity, which was subsequently enlarged and corrected by fellert, Wenzel, Bergman and Guyton-Morveau. The idea that many f-hemical combinations take place in definite proportions only had occurred o some of the older chemists, e.g., Wenzel, Bergman, Kirwan; and they endeavoured to determine these proportions. This view was confirmed by Richter, Proust, Gay-Lussac, Dalton and Berzelius, and expanded into the Theory of Definite l'roportions or Stoichiometry.
I. FUNDAMENTAL NOTION OF AFFINITY. Affinity is that kind of attraction by virtue of which bodies of disimilar nature combine together into a whole which appears perfectly finiform to the senses, even when assisted by the most powerful instruliments. The act of union is called Chemical Combination*, the resulting product a Chemical Comopund, and if it be fluid, a Solution. The dis
* The term Combination is sometimes also applied to the resulting product: the 199 esponding German word Verbindung is applied indiscriminately to the act of com
ition and to the product. [W.]