DE. A. W. HOFMANN ON THE PHOSPHORUS-BASES. 
473 
with solution of potassa, the base is separated from the liquid in oily drops, which are, 
however, readily dissolved on addition of water. The free base, like the corresponding 
monophosphonium- and even monammonium-compounds, cannot therefore be obtained 
in a state fit for analysis ; its formation, however, as well as its conversion into a series 
of well-defined salts corresponding to the dibromide, characterize it as an oxide derived 
fi'om the type. 
Ho 
O 
2 ’ 
as the hydrated dioxide of ethylene-hexethyl-diphosphonium : 
r K p O -[(C2H4y'(C,H5)ePJ'l 
'-"14 ^36 ^2 
H, J 
Complicated as the construction of this compound must appear, the body is remarkable 
for its stability. Its solution may be boiled and considerably concentrated upon the water- 
bath without decomposition, and remains unchanged even when exposed for some time 
under pressure to a temperature of 150°; indeed the decomposition of the hydrate does 
not begin till the liquid is evaporated to dryness. The changes which this compound 
suffers under the influence of higher temperatures are not without interest. They are 
rather intricate, and I propose therefore to devote a special paragraph to their study. 
In its deportment with metallic salts, the hydrate of the diphosphonium closely 
resembles the fixed alkalies, as may be seen from the following Table ; — 
Deportment of the Hydrate of the Diphosphonium with reagents. 
Barium-salts t 
S trontium-salts 
Calcium-salts 
Magnesium-salts 
White precipitates of the hydrates. 
Aluminium-salts 
Chromium-salts . 
Nickel-salts 
Cobalt-salts 
Iron-salts : — 
Ferrosum . . 
Ferricum . . 
Zinc-salts . . 
Lead-salts - 
Silver-salts . 
Mercury-salts : — 
Mercurosum. 
Mercuricum . . 
White precipitate of hydrate of aluminium, soluble in excess of the 
precipitant. 
Green precipitate of hydrate of chromium, soluble in an excess of 
the precipitant, and reprecipitated on ebullition. 
Apple-green precipitate of the hydrate. 
Blue precipitate of the hydrate. 
Greenish precipitate of the hydrate. 
Reddish-brown precipitate of the hydrate. 
White gelatinous precipitate of the hydrate, insoluble iu excess. 
White amorphous precipitate of hydrate of lead, soluble in excess. 
Black-brown precipitate of oxide of silver. 
Black precipitate of the suboxide. 
Yellow precipitate of the oxide. 
3 R 
MDCCCLX. 
