Gaseous diffusion and transport Flashcards
what does FO2 mean
fractional concentration
what does PO2 mean
partial pressure
what does PB mean
barometric pressure
what does PIO2, FIO2 mean
inspired
what does PAO2, FAO2 mean
alveolar
what does PaO2, FaO2 mean
arterial
what does mmHg mean
common pressure unit
(0.133 kPa)
what is SI measured in
kPa
(7.5 mmHg)
What does Dalton’s Law state about partial pressures?
In a mixture of non-reacting gases, the total pressure exerted is equal to the sum of the partial pressures of the individual gases.
What are the components of barometric pressure PB?
- includes all inert gases
How is the partial pressure of oxygen calculated?
What is the fractional concentration of oxygen in dry air?
0.209 (21%).
What is the approximate barometric pressure at sea level?
PB ≈101kPa (760 mmHg).
What is the dry partial pressure of oxygen (PO2) at sea level?
21kPa (159 mmHg).
How does the fractional concentration of oxygen (𝐹𝑂2 ) change with altitude?
remains unchanged at 0.209, regardless of altitude.
What is the approximate barometric pressure at the top of Mount Everest?
33 kPa (250 mmHg).
What happens to 𝑃𝐼𝑂2 with increasing altitude?
How did climbers like Hillary and Tenzing compensate for low 𝑃𝐵 at high altitudes?
They used a high 𝐹𝐼𝑂2 (fraction of inspired oxygen) to compensate for the low barometric pressure.
What is the formula for Henry’s Law?
How does the partial pressure of a gas above a liquid affect the gas dissolved in the liquid?
The higher the partial pressure, the more gas will dissolve in the liquid.
What happens if the pressure above a liquid is released?
Less gas will stay dissolved, and bubbles of gas will rise from the liquid.
What happens when a gas comes in contact with a pure liquid?
Some gas molecules collide with the liquid’s surface and dissolve. A dynamic equilibrium is established when the rate of gas dissolution equals the rate of gas escape into the gas phase.
What happens when the pressure of a gas above a liquid is increased?
The number of gas molecules per unit volume increases, leading to more collisions with the liquid surface and a higher rate of gas dissolution.
What happens to equilibrium when the gas pressure above a liquid increases?
A higher concentration of dissolved gas is achieved until a new dynamic equilibrium is established at the higher pressure.