Chemistry And Physics Flashcards
What is an ionic bond?
Complete transfer of valence electrons
What is a covalent bond?
Equal sharing of valence electrons
What is a polar covalent bond?
Unequal sharing of valence electrons
What is the basic building block that makes up all matter?
Atom
3 components
> protons (positive)
> neutrons ( neutrons)
> electrons (negative charge)
What determines an atom’s atomic number?
Number of protons
What do electrons travel in what?
Predictable orbits called shells
What are electrons in the outermost shell called?
Valence electrons
What happens with a ln incomplete she’ll of elections? What about a complete shell?
Incomplete: reacts with other atoms
Complete: non-reactive (inert)
An atom will have a neutral charge if?
Protons = electrons
An atom will have a positive charge if?
Electrons < protons
An atom will have a negative charge if?
Electrons > protons
What is it called when an atom has either a positive or negative charge?
Ion
An atom that has a positive charge (it lost its electrons) is called a?
Cation
An atom that has a negative charge (it gained electrons) is called?
An anion
What is it called when one pair of electrons is shared? What about 2? What about 3?
Single bond
Double bond
Triple bond
What is a key example of a polar covalent bond?
Water
What is describes as a very weak intermolecular force that holds molecules of the same type together?
Van der Waals Forces
(Electrons orbiting a molecules are in motion > this creates temporary (+) and (-).
What is Dalton’s law?
P1 = P1 + P2 + P3 + Pn
Partial pressure says that the total pressure is equal to the sim of the parti pressures exerted by each gas in the mixture
What is Dalton’s Law?
Total pressure is equal to the sum of the partial pressures exerted by each gas in the mixture
What part of the oxygen delivery equation is MOST affected by Henry’s law?
PaO2
(Henry’s law applies to solubility ~ hence why we multiply the PaO2 by the solubility coefficient
How does partial pressure affect solubility?
> decrease in pressure = a decrease in solubility
> increase in pressure = an increase in solubility
How does temperature affect solubility?
> decrease in temperature = increase solubility
(**this is why anesthetic emergency is prolonged in the hypothermic patient)
> an increase in temperature = decrease in solubility
How many time more soluble is CO2 than O2?
20 times more soluble
(Carbons dioxides coefficient is 0.067 ~ O2 is .003)
What is it called when providers increase the concentration of volatile anesthetic at the alveolocapillary interface to hasten its transfer into the bloodstream?
“Overpressuring” the vaporizer
What is Fick’s law?
Describes the transfer rate of gas through a tissue medium
The rate of transfer (ficks law) is directly proportional to?
Partial pressure difference (driving force)
Diffusion coefficient (solubility)
Membrane surface area
What is the rate of transfer (ficks law) INVERSELY proportional to?
Membrane thickness
Molecular weight
What are some applications of Fick’s law?
Diffusion hypoxia
Calculation of Cardiac output
Drug transfer across the placenta
What does Graham’s law state?
The molecular weight of a gas determines how fast it can diffuse through a membrane
The rate of diffusion is INVERSELY proportional to the square root of the gas’s molecular weight.
What is Boyle’s law?
P1 x V1 = P2 x V2
**inverse relationship (if one variable gets smaller, the other gets smaller)
> constant: temperature
variable: pressure and volume
What is Charles’s law?
V1/T1 = V2/T2
**direct relationships (if one gets bigger, the other gets bigger)
> constant: pressure
variable: temperature and volume
What is Gay-Lussac’s law?
P1/T1 = P2/T2
**direct relationships (if one gets bigger, the other gets bigger)
> constant = volume
variable = temp and pressure
What are some examples of Boyles law?
Diaphragm contraction = increase in tidal volume
Pneumatic bellows
Determining how much is left in a cylinder
What is an example of Charles’s law?
LMA cuff ruptures when placed in autoclave
What is an examples of gay-lussac’s law?
Oxygen tank explodes in heated environment
What is the ideal gas law?
PV = nrT
(Or)
P = T/V (you can reduce it a little)
What is flow defined as?
The mov of electricity, fluid, or air per unit of time.
When comparing hemodynamics to Ohms law, what is current?
Cardiac output (flow)
When comparing hemodynamics to Ohms law, what is voltage difference?
MAP - CVP
(Pressure gradient)
When comparing hemodynamics to Ohms law, what is resistance?
Systemic vascular resistance
What is Poiseuille’s law?
Q = (pie)R^4(change in pressure)/8nL
What exhibits the greatest impact on flow?
Altering the radius
A fluid’s viscosity is inversely proportional to what?
Temperature
> decreased temp increases viscosity and resistance
> increased temp deceases viscosity and resistance
What are the three types of flow?
Laminar, turbulent, and transitional
Laminar flow is dependent on what?
Gas Viscosity!
Turbulent flow is dependent on what?
Gas’s density
What type of flow is < 2000?
Laminar
What are examples of laminar flow?
Airflow in the distal terminal bronchioles
Blood flow in systemic circ
What type of flow is > 4,000?
Turbulent flow
**molecules travel in chaotic pattern
What are examples of turbulent flow?
Orifice (glottis)
High gas flow
Acute angle in the tube
Branching in the tube
(Glottis or medium sized bronchi)
How can we improve airflow in a patient with status asthmaticus?
Because turbulent flow is dependent on density, we can administer a LOWER density gas (heliox) ~ this decrease reynold’s number and improves airflow when resistance is high.
What law describes turbulent flow?
Graham’s!
Turbulent flow is dependent on DENSITY!
What law describes laminar flow?!
Poiseuille’s law!
Flow is dependent on VISCOSITY
When considering Bernoulli’s principle, if the fluid’s velocity is high, what?
The pressure exerted in the walls of the tube will be low
When considering Bernoulli’s principle, if the fluid’s velocity is low, what?
Then the pressure exerted on the walls of the tube will be high
What is the 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 the air is entrained into the tube (Venturi effect)
***adjusting the diameter of the constriction allows for control of the pressure drop and the amount of air that is sucked into the tube
What are some examples of the Venturi effect?
Jet ventilator, Venturi mask, and nebulizer
What is the Coanda effect?
It describes how a jet flow can attach itself to a nearby surface and continue to flow along that surface even when the surface curves away from the initial jet direction
What is the law of Laplace?
Illustrates the relationship b/t wall tension, internal pressure, and radius
What type of force is pressure?
Pushing force > pushes the walls of the object apart
What type of force is tension?
Pulling force
*hold the walls of the object together
What is the equation for the tension of a cylinder shape? (Blood vessels)
Tension = pressure x radius
What is the equation to determine the tension in a spherical shape? (Alveoli, cardiac ventricle, saccular aneurysm)
Tension = pressure x radius /2
What is the equation to determine wall stress in a the heart?
Wall stress = intraventricular pressure x radius / ventricular thickness
What are some things that decrease wall stress?
A decrease intraventricular pressure
A deceased radius
Or an INCREASE in wall thickness
How do we quantify radiation exposure?
Roentgen (R)
What is most radiation exposure the result of?
Scattered x-rays
What is the roentgen equivalent in man?
Rem is used as a dose equivalent
- this relates the human tissue absorption to the effective biological damage of the radiation
What is the yearly radiation max exposure?
5 rem
What is the yearly radiation max for pregnant workers?
0.5 rem
Or 0.05 rem/month
In the non-pregnant person, what is most susceptible to radiation injury?
Eye and thyroid
In the pregnant person, what is most susceptible to injury?
Obvs the fetus
what are the three ways to limit radiation exposure?
Distance
Duration
And shielding
What is the EASiEST way to protect yourself from radiation?
Distance
What is the min safe distance from the radiation source?
6 ft.
What is the equation to determine radiation exposure?
Intensity = 1/distance^2
**the amount of exposure is inversely proportional to the square of the distance of the source.
What is the equation to determine radiation intensity in relation to distance?
Intensity 1/intensity2 =distance2^2/distance1^2
What occurs when vapor pressure equals atmospheric pressure?
Boiling point
Requires an open container
**an increase in atmosphere ~ increase boiling point
A decrease in atmosphere ~ is going to decrease boiling point
What is the process by which a liquid is converted to a gas?
Vaporization
How do modern vaporizes account for the change in temperature in a vaporizer?
They use metals with high thermal conductivity
What is the term adiabatic process?
Describes a process that occurs without gain or loss of energy (heat).
A very rapid expansion or compression of a gas (Joule-Thompson effect)
What is the joule-Thompson effect?
States that a gas stored at high pressure that suddenly released escapes from its container into a vacuum.
It quickly loses speed as well as a significant amount of kinetic energy, resulting in a fall in temperature.
***conversely, rapid compression of a gas intensifies it’s kinetic energy, causing the temperature to rise.
What is critical temperature?
The highest temperature where a gas can exist as a liquid
What is critical pressure?
The minimum pressure required to convert a gas to a liquid at its critical temperature
1 mmHg is equal to how many cm H20?
1.36
What is the melting point of water in kelvin?
273 L
What are the boiling point of water?
373 K
What is the melting point of water? In Celsius
0 Celsius
What is the boiling point of water in Celsius ?
100 Celsius
What is the melting point of water in Fahrenheit?
32 degrees F
What is the boiling point of water in Fahrenheit?
212 F
How do you convert Kelvin to Celsius? And vice versa
Kelvin = 273 + C
C = K - 273
How do you convert b/t Celsius and Fahrenheit? Vice versa
Celsius to Fahrenheit: (C x1.8) + 32
Fahrenheit to Celsius): (F - 32) / 5/9 (or x .55)
What does 1 atm equate to?
760 mmHg
760 torr
1 bar
100 kPa
1,033 cm H2O
14.7 lb/inch^2
What is alvagadro’s number?
1 Mole of any gas is made up of 6.023 x 10^23 atoms
What does a mole of a gas equal?
Weight of that gas in grams
One mole of helium = 4 grams and contains (6.023 x 10^23 atoms)
What is the most effective way to minimize heat loss?
Forced air warmer
What are the four mechanisms of heat loss? In order?
Radiation > convection > evaporation > conduction
What is the afferent limb of the temperature regulation reflex?
Thermodeceptors!
Skin
Deep tissue
Spinal cord
What is the control center in the temperature regulation reflex?
Hypothalamus
>preoptic region
Brainstem
What is the efferent response in the temperature regulation reflex?
Too cold:
>Vasoconstriction
>Piloerection
>Shivering
Too hot:
>vasodilation
>diaphoresis
What is the number 1 source of heat loss?
Radiation (60%!!!)
Most heat is lost through the skin
How much heat is lost via convection?
(15-30%)
Think of convection as wind chill ~ air moves heat that has radiates off body.
How much heat is lost via evaporation?
Aka water loss (20%)
~ think wounds, respiration, exposure during surgery
How much heat is lost via conduction?
This is where heat is lost when the patient comes into contact with a cooler object
**cold OR table, IV fluids, irrigation fluids
Which have experiences that most heat REDISTRIBUTION?
Phase 1. Heat transfers from the central compartments to the peripheral components.
Nominal amount of heat is lost during this process.
When does heat loss exceed heat production?
Phase 2
at what phase does an equilibrium develop between the heat that is lost and heat production?
Phase 3
What is hypothermia defined as?
A core body temp < 36 degrees C
How much does shivering increase oxygen consumption?
400-500%
This is a huge risk of myocardial ischemia and infarction
