Melting 

Solid to liquid state

• Internal KE increases molecular vibrations (when heat is applied)
• Melting point - temp at which solid changes to liquid
  
• Latent heat of fusion- Extra heat (external energy) needed to change solid to liquid
  

Graham's Law

• The rate of diffusion of a gas is inversely proportional to the square root of its gram molecular weight
  
• lighter gases diffuse rapidly, heavy fases diffuse more slowly
  
• At capillary level diffusion moves blood
  
• The lighter the gas the easier the flow
  

Gas density

• The ratio of a substance's mass to its volume
  
• A dense substance has a high atomic weight
  
• A low density substance has a low concentration of light atomic particales per unit of volume
  

Properties of Gases

• Gas pressure - measure of force per unit area
• Tension- the pressure extended by gas when disolved in water

PAir

PAir = pn2 +po2  (pn2=79%+po2=21%)

PA= pressure in avioli

Pa= pressure in artery (po2)

Air is a gas mixture

Dalton's Law

• Total pressure of a gas mixture must equal the sum of all partial pressures of all component gases
• percentage of gas in mixture expressed in decimal form
• Low pressures decrease Pi02
• Hyperbaric pressures increases Pi02
  

Henry's Law

• Predicts how much of a given gas will dissolve in a liquid
• High temp decreases solubility/low temp increases it
• High temp= increased kinetic energy causes more vapor to escape
  

• Solubility coefficient
• volume of gas that will dissolve in 1ml of a given liquid at standard pressure and temp
  

Correction factors

• STPD- Standard temp(0 degrees celcious) and pressure(270mm/hg), air(0%saturated)

• ATPS-Ambient temp(surrounding temp) ,pressure(270mm/hg) and saturated
  
• BTPS-Body temp(37 degrees c ),pressure(270mm/hg) and saturated
  

Gas Behavior

• Critical pressure                                                                   

needed to maintain equillibrium between gas and liquid phases of a substance at this critical temp

• Critical  temperature

The highest temp at which a substance can exist as a liquid

Gas Laws

• Boyle's law   (inversly related)
  B.a.T= temp constant
  
• Charles Law    (Directly related )                                               C.a.P= pressure constant
  
• Gay-lussac's law (Directly related)                                                       G.l.oVe = volume constant (Directly related)                                                       
  

Flow dynamics

• Flow os the bulk movement of a substance through space
  
• Hydrodynamics - study of fluids in motion

• Second law of thermodynamics
  

In any mechanical prosses, there will always be a decrease in the total energy available to do work (potential energy)

Flow patterns

 Laminar flow- Any fluid flowing in a strait pattern changes in tube length, flow of gas, resistance, radius,or viscosity of fluid causes change in driving pressure (Poiseuille's law)

• Turbulent flow ( reynold's law) - Exceeds 2000
• Transitional Flow (mixture of laminar and turbulent flow)
• Law of Continuity (jet nebs)
• The more cross sections the slower the air flow
  

Fluid entrainment

• Bernouli affect

Flowing fluids lateral pressure must inversly with its velocity

• Gas going through a narrow passage increses velocity
• Fluids in an area moving faster than surrounding area posses less pressure

Body Humidity

%BH=ratio of actual water vapor content to gas at body temp (37°c)

%BH=AH/43.8/37°c(100)