ELEMENTS OF MOLECULAR PHYSICS

MOLECULAR PHYSICS. Glossary-1

MOLECULAR PHYSICS. Glossary-2

MOLECULAR PHYICS. Glossary-3.

(1)
(1)

(2)
(2)

(3)
(3)

(4)

(5)

(6)

TO DERIVATION OF CLAUSIUS EQUATION
Calculation of collision number for
molecules on the element of wall at square S.
Elastic collision of molecule with
wall.

(7)

(8)

(9)

(10)

ISOTHERMAL PROCESS (T = const)
pV = const.
T3 > T2 > T1

ISOBARIC PROCESS (V = const)
V3 > V2 > V1

ISOBARIC PROCESS (p = const)
p3 > p2 > p1

(1)

(2)

(3)

THEOREM ABOUT UNIFORM DISTRIBUTION
OF ENERGY ALONG DEGREES OF FREEDOM
For the system of molecules at thermodynamic equilibrium at temperature T the mean kinetic energy of molecules is the same for each degree of freedom and equal to
Molar specific heat capacity of ideal gas:
Monoatomic gas: i = 3 ;
Two-atomic gas: i = 5 ;
Multi-atomic gas: i = 6 .

(1)

(3)

(3)

(1)

(2)

(3)

2r0=d is a diameter of molecule;
F is a force of interaction;
Ep is a potential energy of interaction;
E0 is the energy of connection, or potential well depth
Force of interaction of two gas molecules as the function of distance between their centers
repulsing
attraction

INCREASE OF DISTANCE BETWEEN MOLECULES OF WATER AT VAPORIZING
H2O
Vapor of water
Liquid water
Scale of molecules drawing is 5 x 107.

(1)

(2)

(4)

INTERNAL COMBUSTION ENGINE

THE p-V-DIAGRAMS FOR GASOLINE ENGINE AND FOR DIESEL CYCLE