Unit 12 - Chemistry & Physics Flashcards
complete transfer of valence electrons
ionic bond
equal sharing of valence electrons
covalent bond
unequal sharing of valence electrons
polar covalent bond
3 components of an atom
- protons
- neutrons
- electrons
what 2 components of an atom make up the nucleus?
protons and neutrons
what determines an atom’s atomic number
number of protons
the predictable orbit electrons travel in is called a
shell
electrons in the outermost shell are called
valence electrons
what makes the atom non-reactive (inert)
full shell
what is a molecule?
2 or more atoms bonded together
what gives an atom a neutral charge
electrons = # protons
what gives an atom a positive charge
protons > # electrons
what gives an atom a negative charge
electrons > # protons
what is an ion?
an atom that carries a positive or negative charge
what is a cation
an atom with a positive charge (it has lost electrons)
what is an anion
an atom with a negative charge (it has gained electrons)
which tends to ionize, metals or non-metals?
metals
bond that involves the complete transfer of valence electron(s) from one atom to another
ionic bond
bonding common among acids and bases
ionic bond
key example of a polar covalent bond
water - region near oxygen atom is relatively negative and region near hydrogen atom is relatively positive
what explains why a hydrophilic solute dissolves in water
since water is a polar molecule, it’s also attracted to other polar molecules and ions
what describes a very weak intermolecular force that holds molecules of the same type together
Van der Waals Forces
molecular bonds in decreasing order of strength
covalent > ionic > polar covalent > Van der Waals
Dalton’s law of partial pressures
total pressure is equal to the sum of the partial pressures exerted by each gas in the mixture
how to convert partial pressure to volumes percent for a liquid
volumes % = (volume of solute/volume of solution) / 100
how to convert partial pressure to volumes percent for a gas
volumes % = (partial pressure / total pressure) * 100
convert volumes percent to a partial pressure
partial presure = (volumes %/100) * total pressure
Henry’s law
at a constnt temperature, the amount of gas that dissolves in a solution is directly proportional to partial pressure of that gas over the solution
Or - the higher the gas pressure, the more it will dissolve into a liquid (assuming constant temp)
which law explains why emergence is prolonged in hypothermic patients
why?
Henry’s law
the solubility of the gas is increased and less of it leaves the body per unit of time
according to Henry’s law, how does partial pressure affect solubility?
decreased pressure = decreased solubility
increased pressure = increased solubility
how does temperature affect solubility
decreased temp = increased solubility
increased temp = decreased solubility
solubility of CO2 vs O2
CO2 is ~20 times more soluble than O2
oxygen delivery calculation
DO2 = CO * [(1.34 * Hgb * SpO2) + (PaO2 * 0.003)} * 10
how to calculate the amount of CO2 dissolved in the blood
PaCO2 x 0.067 mL/dL/mmHg
how is most CO2 transported in the blood
in the form of bicarbonate or bound to hgb
how does “overpressurizing” during induction work
if you significantly increase the concentration of volatile anesthetic at the alveolocapillary interface, can hasten its transfer into the bloodstream and ultimately the brain
gas law that describes the transfer rate of gas through a tissue medium
Fick’s law of diffusion
according to Fick’s law, rate of transfer is directly proportional to:
- partial pressure difference (driving force)
- diffusion coefficient (solubility)
- membrane surface area
according to Fick’s law, rate of transfer is inversely proportional to:
- membrane thickness
- molecular weight
law that explains diffusion hypoxia
Fick’s law
law that explains a patient with severe COPD has a reduced alveolar surface area and therefore slower rate of inhalation induction
Fick’s law
law that explains the calculation of cardiac output
Fick’s law
law that explains drug transfer across the placenta
Fick’s law
Graham’s law
molecular weight of a gas determines how fast it can diffuse through a membrane
according to Graham’s law, the rate of diffusion of a gas is inversely proportional to:
the square root of the gas’s molecular weight
law that explains the second gas effect
Graham’s law
Boyle’s law calculation
P1 * V1 = P2 * V2
Charles’s law calculation
V1/T1 = V2/T2
Gay Lussac’s law calculation
P1/T1 = P2/T2
Boyle’s law
at a constant temperature, the volume of a given mass of gas varies inversely with absolute pressure
Charles’ Law
at a constant pressure the volume of a given mass varies directly with the absolute temperature
Gay Lussac’s law
at a constant volume the absolute pressure of a given mass of gas varies directly with the absolute temperature
these are examples of which law:
- pneumatic bellows
- diaphragmatic contraction increases Vt
- squeezing a bag valve mask
- using bourdon pressure gauge to calculate how much O2 is left in a cylinder
Boyle’s law
LMA cuff rupturing when placed in an autoclave is an example of which law
Charles
oxygen tank exploding in a heated environment is an example of which law
Gay-Lussac’s
what is the ideal gas law
unifies Boyle’s, Charles’s, and Gay-Lussac’s laws into a single equation
PV = nrT
- P = pressure
- V = volume
- n = # moles
- r = constant 0.0821 liter-atm/K/mole
- T = temperature
during laminar flow, quadrupling the radius will cause flow to increase by a factor of:
256
Ohm’s law
the current passing through a conductor is directly proportonal to the voltage and inversely proportional to the resistance
Ohm’s law adapted to fluid flow
flow = pressure gradient/resistance
symbol for cardiac output
Q
symbol for SVR
R
Poiseuille’s law
adaptation of Ohm’s law that incorporates vessel diameter, viscocity, and tube length
Q = (π * R^4 * △P) / 8 * η * L
- Q = blood flow
- R = radius
- △P = arteriovenous pressure gradient (Pa-Pv)
- η = viscosity
- L = length of tube
what factor exhibits the greatest impact on flow
radius
how does temperature affect viscocity
inversely proportional
- decreased temp = increased viscosity and resistance
- increased temp = decreased viscosity and resistance
application of Poiseuille’s law to deliver RBCs faster
- increase radius with large bore IV
- increase pressure gradient with pressure bag or raise IV pole
- decrease viscosity by diluting the blood with NS or running through fluid warmer
- use shortest tubing possible
what law explains that polycythemia reduces microvascular flow
Poiseuielle’s
what is Reynolds’ number
allows us to predict the type of flow that will occur in a given situation
Reynolds’ number = (density * diameter * velocity) / viscosity
according to Poiseuille’s law, what is laminar flow dependent on?
gas viscosity
according to Graham’s law, what is turbulent flow dependent on?
gas density
what is laminar flow
- all molecules travel in parallel pattern
- due to cohesive forces, molecules in the center of the tube travel at fastest rate while molecules near walls travel at slowest rate
what 2 things form the nucleus
protons and neurons in the center of the atom
what is avogadro’s number
says that 1 mole of any gas is made up of 6.023 x 10^23 atoms
a mole of gas is equal to the molecular weight of that gas in grams
define specific heat
the amount of heat required to increase the temperature of 1 gram of a substance by 1 degree C
solubility coefficient for oxygen
0.003 mL/dL/mmHg
solubility coefficient for CO2
0.067 mL/dL/mmHg
How does knowing the oxygen solubility coefficient help us calculate oxygen delivery?
Multiplying the Pa02 by oxygen’s solubility coefficient
(0.003 mL/dL/mmHg) allows us to calculate how much oxygen is dissolved in the blood.
List 4 clinical examples of
Fick’s law
- Diffusion hypoxia
- A patient with severe COPD has a slower rate of inhalation induction
- Calculation of cardiac output
- Drug transfer across the placenta
formula for Boyle’s law
P1 * V1 = P2 * V2
formula for charles law
(V1/T1 = (V2/T2)
formula for gay-lussacs law
(P1/T1) = (P2/T2)
how does use of Heliox decrease airway resistance
turbulent flow is primarily dependent on gas density
inhaling lower density gas decreases Reynold’s number and improves flow turbulence when airway resistance is high
examples of laminar flow
- airflow in terminal bronchioles
- systemic blood flow
Re in terminal bronchioles
low (< 2000)
laminar flow
Re in terminal bronchioles
low (< 2000)
laminar flow
examples of Re > 4000
turbulent flow
* flow through orifice (glottis or annular space when FGF is high)
* airflow through medium-sized bronchi
Bernoulli’s principle
describes the relationship between the pressure and velocity of a moving fluid or gas
how does velocity affect pressure according to Bernoullis principle
- If the fluid’s velocity is high, then the pressure exerted on the walls of the tube will be low.
- If the fluid’s velocity is low, then the pressure exerted on the walls of the tube will be high.
Venturi effect
As airflow in a tube moves past the point
of constriction, the pressure at the constriction decreases (Bernoulli principle). If the pressure inside
the tube falls below atmospheric pressure, then air is entrained into the tube (Venturi effect)
examples of venturi effect
Jet ventilator, Venturi mask, and nebulizer
describes how a jet flow attaches itself to a nearby surface and continues to flow along that surface even when the surface curves away from the initial jet direction
Coanda effect
ex of coanda effect
Wall-hugging jet of mitral regurgitation and water that follows the curve of a glass
illustrates the relationship between the wall tension, internal pressure, and radius
law of Laplace
law of laplace equation applied to cylinders
tension = pressure * radius
law of laplace equation applied to sphere
tension = (pressure * radius) / 2
according to the law of laplace, the tendency of an alveolus to collapse is directly proportional to:
surface tension
(more tension = more likely to collapse)
according to the law of laplace, the tendency of an alveolus to collapse is inversely proportional to:
alveolar radius
(smaller radius = more like to collapse)
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