16 The Philippine Journal of Science. 1921 
Cl 
] 
H3N | NH; ‘ade 
Ro oF re 
Py. 
rey ess 
H3N | NHs ~>-~ 
Cl Gi 
THE CARBON GROUP 
| | ul ul | 
oa a hae (Ge ), Sn Fes ee 
(ap 
(—Pb—). 
Vacancies in shell — 4. 
There is unmistakable evidence that there are definitely four 
vacancies in the shell of each of these atoms. Sn" and Pb" 
are predominantly electropositive; but, as the relation of these 
atoms to the “inert group” has been established by physical evi- 
dence, each containing 4 less electrons than the corresponding 
inert atom, we have good reason to believe that this fact plays 
a large part in determining their chemical properties. This idea 
: | 
is substantiated by the behavior of — es —and — Pb— in 
| 
organic compounds. 
The ordinary carbon-hydrogen-oxygen compounds are ex- 
pressed in the proposed system exactly in the same manner as is 
customary among organic chemists. The peculiar compound CO, 
however, has never been successfully explained except by Lang- 
muir’s hypothesis that the two kernels share 5 pairs of electrons, 
1 pair being held rather closely by the kernels and the other 4 
pairs in an octet external to both kernels. In this case the va- 
lence of each atom is increased by 2, because a stable arrange- 
ment of 10, instead of 8, shell electrons is formed. 
EXAMPLES 
cago U=C=6°% 0-0-2 o 
H Cl 
ta | ; | 
Sn === @|- H—Ge—H Cl— Sn—Cl 
| 
H Cl 
