11] IONIZATION THEORY OF GASES 51 
Boe Oe, : : 
Ne=2— *™ electrostatic units, 
where wu, is the velocity for 1 volt (7.e. 34, E.S. unit) per cm. 
It is known that one absolute electro-magnetic unit of 
electricity in passing through water liberates 1:23 c.c. of hydrogen 
at a temperature of 15°C. and standard pressure. The number of 
atoms in this volume is 2-46 N, and, if e’ is the charge on the 
hydrogen atom in the electrolysis of water, 
2:46 Ne =3 x 10” £.S. units, 
ING! 3 MA Se MOONS, (Sh hoboUN ESS 
Thus f= 246 x 10-23. 
e K 
For example, substituting the values of wu, and K determined 
for moist air for the positive ion, 
e 246 137 
—_ = —~A-___ ——— =|: es 
Zim KOON 0320 ae 
Values of this ratio, not very different from unity, are obtained 
for the positive and negative ions of the gases hydrogen, oxygen, 
and carbon dioxide. Taking into consideration the uncertainty in 
the experimental values of u, and K, these results indicate that the 
charge carried by an ion in all gases is the same and is equal to 
that carried by the hydrogen ion in the electrolysis of liquids. 
39. Number of the ions. We have seen that, from experi- 
mental data, Townsend has found that WV, the number of molecules 
present in 1 cc. of gas at 15°C. and standard pressure, is given by 
ING WDD Se 
Now e, the charge on an ion, is equal to 3-4 x 10~” E.s. units. 
Thus IN 3:06 10! 
If J is the saturation current through a gas, and q the total 
rate of production of ions in the gas, 
Eee 
