Page:Text-book of Electrochemistry.djvu/175

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��DEGREE OF DISSOCIATION.

��CHAP.

��of molecules dissolved is greater than that calculated simply from the chemical formula. Now, if a molecule can be dis- sociated into n ions (for KCl = K + CI, w = 2 ; for K2SO4 = 2K + S04,7i= 3; for K4(CN)6re = 4K + (ON)6Fe,7i = 5), and if as denotes the fraction of the whole number of mole- cules which are dissociated, then in the solution there must be for every gram-molecule dissolved 1 — aa undissociated molecules and a^n ions, which are to be regarded as free molecules. From every gram-molecule, therefore, we obtain 1 — aa + Tiaa = 1 + (w — l)aa molecules, and the observed freezing point — A° must be greater than that calculated

1 Q.gO

according to the chemical formula — ^ - in this ratio (/). That is to say —

from which aa can be calculated.

��Noii-«lectrolyte8.

��Methyl •loohol Ethyl aloohol. Batyl alcohol Glyoerol •. Mannitol. . Cane sugar. Phenol. . Acetone. . Ethyl ether. Ethyl acetate. ▲cetamlde. .

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��0^ 0^ 0- 0- 0- 0- 0- 0- O'OT ■OS

��0^ 0^ 0- 0- 0- 0- 0- 0-

��Baaes.

�� �Acids.

� �aa

� �«!

�Q-6b

�Hydrochloric add

�Nitric add. .

�0-0*i

�Chloric add. .

�Sulphuric add

�0-OL

�Phosphoric acid.

�Hydrogen sulphide

�Boric acid. ..

�Formic add. .

�Butyric add. .

�Oxalic add. .

�OIJ

�Malic add. ..

��0- 0- 0^ 0^ 0- 0'

��SalU.

��Potassium chloride. Potassium nitrate Sodium nitrate. Potassium acetate Potassium carbonate Potassium sulphate ,

��0-8G

��Salts.

��Barium chloride Lead nitrate. Copper sulphate Mercuric chloride Cadmium iodide

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�a-i

�Oil

�- •(>

��In dilute solution, too, unexpected results have been obtained. These, however, are to be attributed for the most

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