184 F. W. Clarke on Atomic volumes of Liquids. 
Kopp’s numbers for the first two, the atomic volume of phospho 
rus is found respectively as follows: 25°5, 25-2, 26-2, 25°8, 224, 
25°5, 26°1, 23°2, 29°3, 32°3, 27:1, 27-1, and 19-7. The average 
of these, 25:8, agrees very closely with Kopp’s numbers, and 
varies only 0:4 from the average obtained for boron. 7 
he atomic volume of arsenic I have deduced from the vapor — 
volumes of three of its compounds exclusive of the chlorid 
In the chlorid the element has the atomic volume 26°4, (Kopp) 
and in triethyl arsine, triethyl arsenite, and triethyl arsenate, 1 — 
obtain the numbers 25°5, 2u°7, and 292. The average of all 
four numbers is 26°9. 
we get the number 25°8. To these three elements we can prob- 
ably add vanadium, which Roscoe has shown belongs m the 
same group. There is but one liquid compound of this metal 
for which I had data to calculate from,—the oxychlorid, Rot 
coe’s “vanadyl trichlorid,” VOCI,. Calculating its vap% 
volume, and thence the atomic volume of vanadium, I tained : 
fhe number 27.4. 4 
It will be seen that a number of compounds of boron, phot 
phorus, and arsenic gave higher results than this, and therefor, 
for a single compound, this number seems close enough to that 
found for the other three elements, to be classed with the — 
This view is somewhat strengthened by the fact that the atom? | 
weight of vanadium is intermediate between those of phosph 
rus and arsenic. 
ume of antimony from these, we get the numbers 329 and 
_ 83-4, In addition to these I have determined from their val" | 
ly : 
bers 33°3, 32°1, 32°9, and 35°9. Adding in these wl 
numbers from the chlorid and bromid of the metal, We 
In the case of bismuth there is but one liquid compoun® | 
which I had the necessary data, Triethyl Tsonthi has 
vapor volume 138, while triethyl stibine has the number _ 
These are so near together that it seems probable that bis™ 
m its — compounds has the same atomic volume as ae 
a ut more data are needed to decide this point 
. 
