88 Experiments on the Oxide and Salts of Uranium. 
IJ. Oxide of uranium dissolves easily and entirely in muriatic 
acid, and the solution affords, on evaporation, very deliquescent 
prismatic crystals, of an olive-green colour; if these be dried 
by heat, they suffer decomposition; but when dried in the 
exhausted receiver, by sulphuric acid, they crumbled down into 
a dirty green powder, which is extremely deliquescent. To 
ascertain the composition of this salt, a portion of the neutral 
muriate was decomposed by caustic ammonia, and the preci- 
pitated oxide dried, ignited, and weighed, amounted to 112 
grains. The filtered ammonio-muriatic solution was rendered 
slightly acid by nitric acid, and precipitated by nitrate of silver; 
it afforded 149.8 grains of chloride of silver, equal to 38 grains 
of muriatic acid. Here, therefore, the muriate of uranium ap- 
pears to consist of— 
Oxide ofuranium . 112 . . 100 
Muriatic acid . . 38 . . 34 
Assuming this muriate to consist of 1 proportional of muria- 
uc acid, 37, and 1 of oxide of uranium, the equivalent of the 
latter will be 109, and that of the metal 101. 
III. The recently precipitated oxide of uranium very readily 
dissolves in nitric acid, and, by careful evaporation, furnishes 
truncated prismatic crystals ofa peculiar iridescent appearance, 
a brownish-yellow colour, and deliquescent. A portion of these 
crystals, exposed under the exhausted receiver containing sul- 
phuric acid, effloresced into a yellow powder, which was re~ 
tained in vacuo till it ceased to lose weight; 60 grains were 
then submitted toa red heat, in a platinum capsule, and 36.4 
grains of oxide remained. If, therefore, we regard the above 
salt as a dry nitrate, it will consist of 
36.4 oxide of uranium =60.7 
23.6 nitricacid . . =39.3 
100. 
and if considered as a compound of 1 proportional of nitric 
acid, and 1 of oxide of uranium, the number 84 will represent 
the oxide, and 76 the metal; but we can put no further reliance 
in the above numbers than as showing the quantity of oxide 
