ELECTROLYSIS OF SECONDARY COMPOUNDS. 
17 
ammonia and nitric acid, it was decidedly shown that a portion of the acid had 
travelled to the zincode cell. 
Neutral chromate of potassa (KO, Cr0 3 ), which contains an acid forming no definite 
hydrate with water, furnished a perfectly analogous result ; and the same thing was 
observed in the experiments with arsenite of potassa. 
(a. g .) The carbonic acid is one of those which seems to have the least affinity for 
water, but it has been already shown that in the electrolysis of the carbonates of 
potassa, soda and ammonia, it is given off as oxy-carbion at the zincode in equivalent 
proportions. We now repeated the experiment. The diaphragm cell was charged 
throughout with carbonate of soda (NaO, C0 2 ) of definite strength, and the gas tube 
from the zincode cell connected with a drying apparatus, and Liebig’s bulbs. The 
amount of carbonic acid was ascertained by weighing the bulbs, and by careful pre- 
cipitation of the liquid in the cell by caustic ammonia and chloride of barium. By 
these means it was ascertained that there had been a decided transfer of the acid to 
the zincode, though in much less proportion than that of the sodium to the platinode. 
From the quantities of acid transferred in these experiments (which quantities how- 
ever, as they can be considered but approximations to accuracy, we have not thought 
it necessary to record), it would appear that those acids which form no definite 
hydrates, are transferred to the zincode in smaller quantity than is the case with 
those from which distinct hydrates are obtainable. 
(a. h .) We were extremely anxious to devise some means of ascertaining the phe- 
nomena of transfer in the case of simple electrolysis, but were forced to abandon the 
attempt after many trials, from the difficulty of procuring any substance which would 
answer the purpose of a permeable diaphragm, whilst it could resist the heat which 
is necessary to bring the chlorides, or similar binary compounds into the liquid state. 
We, however, ascertained that when a solution of chloride of sodium in water was 
electrolysed, the chlorine was transferred to the zincode in greater quantity than the 
sodium from it. 
(a. i .) To remove the possibility of its being thought that water in these experi- 
ments conveyed the force independently of the presence of the saline bodies (a sup- 
position hardly reconcilable with the phenomena observed where the saline solution 
was used throughout the apparatus), the following experiments were made. The 
platinode cell of the diaphragm apparatus was charged with dilute sulphuric acid, 
and the zincode with distilled water ; one diaphragm alone was employed. The 
arrangement conducted so badly, that in an hour and a half, with twenty cells of the 
battery, only 15 cubic inch of hydrogen was collected from the platinode. The 
apparatus was then recharged and the electrodes reversed, the water being now at 
the platinode, and the acid at the zincode. In an hour and a half 2 - 8 cubic inches 
of hydrogen were collected from the platinode. From the imperfect conducting- 
power evinced by water in these and other experiments, we can hardly suppose that 
the current, in cases where the base is not transferred, is carried by the electro- 
MDCCCXLIV. D 
