Chemistry and Physics Flashcards
What is an ionic bond?
Complete transfer of valence electron, leaving one atom with a positive charge and the other with a negative charge
Which types of compounds tend to form ionic bonds?
Metals
Acids
Bases
Describe covalent bonds
Sharing of an electron between two atoms. Can be single or double bonded
Describe polar covalent bonds
The shared electron is held more closely by one atom than the other, creating a negative and a positive end (e.g. water)
What are van der Waal’s forces?
very weak intermolecular forces that hold similar molecules together
List the types of molecular bonds in order from strongest to weakest
Ionic > Covalent > H2 > VdW
Describe Dalton’s Law
Partial Pressures
What determines an atom’s atomic number?
The number of protons
Describe Henry’s Law
Solubility is directly proportional to partial pressure of that gas over the solution
What are the applications of Henry’s Law?
Overpressuring the vaporizer
Increasing the FiO2 to increase PaO2
Describe Fick’s Law
Diffusion through a tissue medium
What are the applications of Fick’s Law?
Cardiac output calculation
Placental drug transfer
What are the applications of Graham’s Law?
second gas effect
turbulence of gas flow through annular space is dependent on the gas’s density
Describe Graham’s Law
“Graham talks about grams”
the molecular weight of a gas determines how quickly it can diffuse through a membrane
Smaller molecules diffuse faster than larger molecules
Describe Boyle’s Law
Volume and Pressure and inversely proportional
What are applications of Boyle’s Law?
Pneumatic Bellows
the Diaphragm
What is Charles’ Law?
Temperature and Volume
are directly proportional
Describe Gay-Lussac’s Law
Temperature and Pressure
are directly proportional
What is the ideal gas law?
Combines Boyles/Charles/GL laws
PV = nRT
OR
P = T/V
Describe Ohm’s Law
Describe Poiseuille’s Law
modification of Ohm’s law that incorporates vessel length, diameter, and viscosity
Doubling the radius increases flow by:
16x
Tripling the radius increases flow by:
81x
What are applications of Poiseuille’s Law?
Anything relating:
Vessel size (Selecting a large bore IV)
Viscosity (Polycythemia decreases flow)
and diameter (Carotid stenosis reduces flow)
Laminar flow is dependent on:
gas viscosity (this is Poiseuille’s law)
Turbulent flow is determined by:
gas density (this is Graham’s Law: the speed with which a gas moves is inversely related to its density)
Turbulent: Graham’s
Laminar: Pouiseille’s
Gas flow through the ______ is laminar
terminal bronchioles
Gas flow through the ______ is turbulent
Glottis
carina
Medium Bronchioles
Laminar flow occurs with a Re of _________
< 2000
Turbulent flow occurs with a Re of ________
> 4000
Turbulent flow tends to be created by:
Change in orifice to a narrow diameter
High gas flow
Acute angle in the tube
Branching in the tube
Why does heliox improve flow?
Turbulent flow (created during an asthma attack) is dependent on gas density. We use a lower density gas to increase laminar flow
When is helium not helpful?
If flow is already laminar it won’t make any difference
The venturi effect is an application of ______
The bernoulli principle
Describe Bernoulli’s principle
If a fluid’s velocity is high, the pressure exerted on the walls will be low
If a fluid’s velocity is low, the pressure exerted on the walls will be high
Describe the Venturi effect
As airflow in a tube moves past a point of constriction , the pressure decreases below atmospheric pressure, entraining more air
What are clinical applications of the Venturi effect?
Jet ventilation
Venturi mask
nebulizers
What is the Coanda effect?
Jet flow tends to attach itself to a nearby surface and flow along that surface, even after if curves away from the initial flow
What is a clinical example of the coanda effect?
the wall-hugging jets that develop in mitral regurgitation
Bernoulli
Venturi
Coanda
Describe the inverse square law
The amount of radiation exposure is inversely proportional to the square of the distance of the sources
What are the three ways to limit exposure to radiation?
Distance
Duration
Shielding
The minimum safe distance from a radiation source is:
6 feet
What is a roentgen?
How we quantify exposure
what is rem?
The roentgen equivalent in man
Relates the amount of exposure to the effective likely biological damage
What is the yearly maximum radiation exposure for adults?
5 rem
In a nonpregnant person which organs are most susceptible to damage from radiation?
The eye and the thyroid
What is the latent heat of evaporation?
calories required to convert 1g of liquid to vapor WITHOUT a temperature change
What is the boiling point?
temperature at which vapor pressure is equal to atmospheric pressure
What is specific heat?
Amount of heat required to increase the temperature of 1g of a substance by 1 degree C
What is critical temperature?
Highest temperature a gas can exist as a liquid
How do you convert between Kelvin and Celsius?
How do you convert Celsius to Fahrenheit?
1 cm H20 = __ mmHg
0.74 mmHg
1mmHg = ____ cmH2O
1.36 cm H2O
1 atm =
What is Avogadro’s number?
6.02 x 10 ^ 23
What is the law of LaPlace in spheres and cylinders?
