# 19. Equation of State and Basic Thermodynamic Processes

version from 2016-02-04 19:35

## Section

1. An ideal gas is a gas that obeys all gas laws exactly
2. An ideal gas can be compressed without limit because it is presumed that the molecules take up negligible space

## The Ideal Gas Equation

pPressure (Pa)
VVolume (m^3)
nAmount of Sub. (mol)
RUniversal Gas Constant (8.314J.K^-1)
TAbsolute Temperature (K)

This equation is only exact for the equilibrium state of an ideal gas.
To describe a real gas, there is the...

## van der Waals equation:

pPressure (Pa)
VVolume (m^3)
nAmount of Sub. (mol)
RUniversal Gas Constant (8.314J.K^-1)
TAbsolute Temperature (K)
aempirical constant related to v.d.W forces between gas molecules
bempirical constant, volume of 1mol of gas in liquid state

## There are 4 Thermodynamic Processes

NameCharacteristicConnected Law
IsothermalTemperature is constant.Expressed by Boyle's Law p.V = Constant
IsobaricPressure is constant.Expressed by Gay-Lussac's Law V/T = Constant
IsochoricVolume is Constant.Expressed by Gay-Lussac's law p/T = Constant
AdiabaticEntropy is constant.System can't transfer heat with surroundings. p.V^k