MICRO AND NANOSCALE SYSTEMS - Foundations of Nanotechnology: Pore Size in Carbon-Based Nano-Adsorbents - page 182

TABLE 2.1 The Molecular Weight of Some Gases

gas ammonia air

Ar

N CO

H 2 O 2 CO 2

m 28 40 2 32 28 44 17 29

Therefore, the internal pressure is proportional to the square of the con-

centration n :

,

where, r-the gas density.
Thus, the total pressure consists of internal and external pressures:

a

pp

+ =+

p v

H 2

Equation (2.3) is the most common for an ideal gas.
Under normal physical conditions

, and then from Eq. (2.3) we obtain:

Knowing R we can find the gas constant for any gas with the help of the
value of its molecular mass m (Table 2.1):
8314

R = mm
For gas mixture with mass M state equation has the form:

8314 MT

pv  MR T 

CM

(2.4)

ì

CM

where -gas constant of the mixture.
The gas mixture can be given by the mass proportions g i , voluminous r i or
mole fractions n i , respectively, which are defined as the ratio of mass m i , volume
v i or number of moles N i of i gas to total mass M , volume v or number of moles
N of gas mixture. Mass fraction of component is

m

i

i = 1 n

g i =

, where . It is

M