GAS
PRESSURE AND ITS MEASUREMENT 

Pressure 

Units of pressure 

Measuring pressure 


Atmospheric pressure 


Pressure of gases 



Closedtube manometer 



Openended manometer 
EMPIRICAL
GAS LAWS 

Boyle’s Law:
PressureVolume relationship 

Charles’ Law: TemperatureVolume
relationship 

GayLussac’s Law:
TemperaturePressure relationship 

Avogadro’s Law:
QuantityVolume relationship 
DERIVED
GAS LAWS 

Combined Gas Law 

Ideal Gas Law 


Mathematical derivation 


Calculations using the Ideal Gas
Law 



Calculations involving just P, V,
n, and T 



Calculations involving mass or molar mass,
P, V, n, and T 



Calculations involving density and molar mass 
STOICHIOMETRY
AND THE IDEAL GAS LAW 
GAS
MIXTURES 

Partial pressures and mole
fractions 


Dalton’s Law of Partial Pressures 


Partial pressure 


Mole fraction 


Relationship between mole fraction
and partial pressure 

Gases collected over water 
KINETIC
THEORY 

Definition 

The five postulates of the Kinetic
Theory of Ideal Gases 


Gases are composed of particles,
atoms or molecules, whose size can be considered to be negligible. 


Gas particles are in continuous
random motion. 


The attractive forces between
particles have a negligible effect on their behavior. 


Collisions between gas particles
are elastic. 


The average kinetic energy of a
particle is directly proportional to the absolute temperature. 
EXPLAINING
THE GAS LAWS FROM THE KINETIC THEORY 

Explaining GayLussac’s Law 

Explaining Boyle’s Law 

Explaining Charles’ Law 

Explaining Avogadro’s Law 

Explaining the Ideal Gas Law 
DIFFUSION
AND EFFUSION AND THE KINETIC THEORY 

Diffusion 

Effusion 

Graham’s Law 

Rootmeansquare molecular speed 
REAL GASES 

Conditions under which real gases
deviate from ideal gases 


Two assumptions that do not hold
true for real gases 



That the volume of the gas particles themselves
is effectively zero 



That there is no force of attraction between
gas particles 


Two conditions under which the
behavior of real gases deviate significantly from the behavior of ideal
gases. 



High pressure 



Low temperature 


In general, the closer a gas is to
the liquid state the more it will deviate from the Ideal Gas Law. 

Real gases adhere to a corrected
form of the Ideal Gas Law Equation called the van der Waals Equation. 



