MEECUEIC, STAjS^NIC, AND PLUMBIC ETHYLS. 
419 
faint ethereal odour. Its specific gravity is 2-46. It burns with a smoky flame, more 
lummous than that of mercuric methyl, and disengages at the same time much mercu- 
rial vapour. It is very insoluble in water, less so in alcohol, but readily soluble in ether. 
Towards concentrated sulphuric and hydrochloric acids, mercuric ethyl follows the 
deportment of its homologue, mercuric methyl. When the action is assisted by a gentle 
heat, hydride of ethyl is disengaged, and the crystalline sulphate or chloride of mercu- 
rous ethyl is produced in colourless plates. The radical bursts into spontaneous ignition 
when poured into a jar of chlorine gas, and the mercury is principally converted into 
chloride. With bromine and iodine also the action is violent; but if the action be con- 
ducted under water, ethyl gas or its products of decomposition are eliminated. 
With a freezing mixture to moderate the reaction, the nascent ethyl gas unites with 
excess of bromine ; and by distillation, bromide of ethyl may be obtained, 
These changes may be represented by the equations — 
4 
(Hg C, H,)-f H, S, 03=2(Hg3 C, H,) S 0,-f 2(C, H, H) 
V ] ' V — ^ '• V ^ 
Mercuric Sulphate of Hydride of 
ethyl. mercurous ethyl. ethyl. 
2(Hg C, H,)+2Br=Hg3 C, H, Br+C, H, Br 
' y ) 
Mercuric Bromide of Bromide of 
ethyl. mercurous ethyl. ethyl. 
If the vapour of mercuric ethyl be heated to about 226°, it is suddenly decomposed 
with a slight explosion, into mercury and an inflammable gas. This gas has not been 
analysed ; hut from reasons deduced from the behaviour of sodium towards this radical. 
there seems to be little doubt of its being a mixture of ethylene and hydride of ethyl, 
the results of a splitting up of a double molecule of ethyl. 
From this tendency to decomposition at a high temperature, considerable difficulty 
was experienced in obtaining accurate numbers for the vapour-density of mercuric ethyl. 
In one experiment the apparatus was shattered by employing heat to fill the glass balloon 
with liquid, the mixture with air causing a loud detonation. This difficulty was easily 
overcome by inverting and dipping the mouth of the balloon in liquid, partially exhaust- 
ing the air, and then causing the liquid to rise by atmospheric pressure. It is also 
necessary to draw the neck of the balloon very fine ; otherwise the heat during sealing 
will infallibly cause a decomposition throughout the whole of the vapour. 
Grrammes. 
Weight of globe filled with vapour . 16*0895 
Weight of globe filled with air . . 15*3530 
P= 0*7365 
Pressure. Temperature, 
767*60 mm. 194° C. 
766*48 mm. 14°C. 
Capacity of the globe =V=118*75 cubic centimetres. 
Volume of mercury entering the globe= 117*25 cubic centimetres. 
Difference ='yi=: 1*50 
=weight of one cubic centimetre of air at 14° C. = 0*001230, 
^/'=weight of one cubic centimetre of air at 194° C. =0*000755, 
