Chem final Flashcards
Farenheit to Celcius
C= (F-32) x 5/9
Celcius to Farenheit
F= (C x 9/5) + 32
Force equation
force= mass x acceleration
Avogadro’s number
1 mole= 6.022 x 10^23
What is an atom?
it is the smallest unit of an element that still maintains the characteristics of the element (electron, proton, neutrons)
What is a molecule?
2 or more atoms that are chemically joined together; smallest unit that retains the physical and chemical properties of the substance (H2O, N2, O2)
What is an element?
a substance that cannot be separated into a smaller substance by chemical means; pure! examples include oxygen, nitrogen, and carbon
What is a compound?
contains atoms of different compounds chemically bound together in a fixed ratio; a molecule that contains at least two different elements
What is a physical change?
a simple change of state of matter (solid to liquid to gas)
What is a chemical change?
a change in the composition of matter, atoms, or molecules of 2 or more substances rearrange to form 2 or more new substances having different properties
Understand the relationship between gravity, mass, and weight.
Mass: a given quantity of matter in an object
Weight: the force acting on matter determines the weight
in space, we would have the same mass but we would be weightless because there is no gravity acting on matter in space
What is the difference between adhesive and cohesive forces?
adhesive: like to unlike molecules; water will climb up the sides of glass
Cohesive: like to like molecules; molecules exhibit a force of mutual attraction; water will attract towards itself and away from the glass in a beaker
What is the octect rule?
there will always try to be 8 molecules that exist in the outer shell
Describe covalent and ionic bonding.
covalent bonding is the sharing of electrons; it is the strongest bond type
ionic is the donation or acceptance of electrons to another molecule or compound
How much volume does 1 mole of gas occupy at STP?
22.4 L
The chemical properties of water that make it a good solvent for polar compounds
less dense in it’s solid state (when frozen), dipole, universal solvent, high BP/MP, latent heat and heat of vaporization, water dissociates into H+ and OH- which contributes to acid base balance
Electrons spend more time orbiting 0 than H. Dipoles exist when atoms of different electronegativities are bonded together. The solute in water with a charge will be attracted to the dipole of the water molecule. If something is not charged, it will not be attracted to the water and will not easily be “surrounded” by the water. Since oxygen has a higher electronegativity than hydrogen, the side of the molecule with the oxygen atom has a partial negative charge. A molecule with such a charge difference is called a dipole
Know how the subatomic particles contribute to mass
protons and neutrons (approx 1 amu) are really the only subatomic particles that contribute to mass since electrons have an insignificant mass
What is an isotope?
an isotope is an element that has the same number of protons but a different number of neutrons
What is nuclear radiation?
Ionizing radiation happens when an unstable atom (a radioactive isotope of an element) emits particles or waves of particles to become more stable. This process is called radioactive decay.
How does pK relate to onset time of an anesthetic?
the more unionized a drug is, the quicker the onset
is is the primary determinant of onset time
How does the unionized form of an anesthetic contribute to creating a conduction block?
it is the unprotonated, uncharged, base (B)- diffuses more easily through the nerve sheath, is required for diffusion into neuron; reflected clinically as onset of anesthesia
How does the ionized form of an anesthetic contribute to creating a conduction block?
binds to receptor site on the inside of cell membrane, responsible for suppression of the action potential; reflected clinically by the profoundness of the block
What are the determinants of blood pH?
strong ion difference, weak acids, pCO2, and dissociation of water
Hydrogen bonding
a special dipole-dipole where H binds to N, O, or F of another molecule
LDF bonding or Van der Waals
momentary attractions, not even official bonding; the longer the chain, the more likely LDFs will form
Dipole-dipole
when charged end of one molecule is attracted to the negative end of another molecule
What is an acid?
an acid (pitcher) is an electron donor
What is a base?
a base (catcher) is an electron acceptor
What is the difference between weak acids and strong acids?
with weak acids the equation can be reversed (goes in both directions)
With strong acids the equation can only go one way; it completely dissociates
Examples of weak acids include:
Hprotein, carbonic acid, phosphoric acid
Comment on the ionization and other properties of a protonated acid.
protonated, unionized, liphophillic, crosses membrane, active, hydrophobic
Comment on the ionization and other properties of a protonated base.
protonated, ionized, hydrophillic, will not cross membranes, inactive, liphophobic
The onset of an anesthetic is determined by
the pK, the more unionized a drug is, the faster the onset time
How are the ionized and unionized form of a local anesthetic involved in the process of producing a conduction block?
unionized- onset time
ionized- reflected by the profoundness of the block
What is the CO2 hydration reaction?
CO2+ H2o H2CO3 HCO3- + H+
The determinants of blood pH are:
strong ion difference, weak acids, pCO2, and dissociation of water
Weak acid buffers include:
hemoglobin, proteins, and phosphate
Strong acids include
lactate, keto acids, and sulfate
Force equation
force= mass x acceleration
kg x m/s^2
measured in Newtons or Dynes
Work equation
work= force x distance
kg x m^2/s^2
Result is Joules
Potential energy equation
Potential energy= height x gravity x mass
m x 9.8 m/s2 x kg
Result is Joules
Power equation
Power= work/time
Joules/sec. (WATTS!)
Absolute 0’s for Kelvin, celcius, and farenheit
Kelvin: 0
Celcius: -273
Far: -459
Reynold’s number equation
velocity x density x diameter/viscosity
When gas is turbulent, this is determinant of flow
density
it influences the probability that interactions between fluid molecules will occur
obeys Graham’s law
When gas is laminar, this is the determinant of flow
viscosity
obeys Pouisellie’s law
What is Pouiselle’s Law?
Flow = pi x r^4 x delta p/ 8 x viscosity x length
Solubility of solid in a solution
the greater the temperature of the solvent, the greater the amount of solid solute dissolved (usually)
Solubility of gases in a solution
the greater the temperature of the solvent, the less gas will be dissolved in the solvent
Henry’s law:
C= P (in)/ Kh (out)
Graham’s Law:
diffusion coefficient= solubility of gas/ square root of GMW
Fick’s Law:
diffusion rate= area x diffusion coefficient x P1-P2/thickness
Law of Laplace:
cylinder: T= PR
sphere: 2T= PR
Heat is equal to
Heat = I^2/area
Electromagnetic wave properties:
possess both wavelength and frequency
Each wave is energy so if the wavelength is shorter then it means there is more energy
Wave Particle duality theory
EMR travels as photons of energy and can be thought of as a particle and a wave depending on how it is observed and measured
EMR propagates as:
a wave & a particle
The energy of EMR is
inversely proportional to its wavelength
short wavelength/high frequency= high energy
long wavelength/low frequency= low energy
When EMR is quantized this means that
it is emitted in discrete quantities of energy
EMR energy is characterized by the energy of the photon (energy is greater for photons of higher frequency)
The wavelength is
the distance between peak to peak or trough to trough
The relationship between wavelength and frequency
Wavelength and frequency are inverse of each other
EM waves represent propagation of
energy from a source
it follows the inverse square law 1/d^2
it will dissipate as distance increases
The absorbed dose is
the amount of energy deposited for unit of mass
the equivalent dose is
the absorbed dose multiplied by a converting factor based on the biologic effects of the type of energy
The roentegen equivalent man (rem)
is the amount of ionizing radiation required to produce the same biological effect as one rad of high penetration X-rays
milliroentgen= mrem
The variable number of neutrons in the nucleus of an atom (isotopes)
leads to the process of nuclear decay that produces radiation
it will have a tendency to spontaneously rearrange itself into a new combination of particles which are more stable- decay process
During the decay process
bundles of excess energy (radiation) are emitted from the nucleus in several ways: beta, alpha, and gamma radiation
all of these are ionizing
Beta particle radiation occurs when
the neutrons are excessive, a neutron can convert itself to a proton and an electron. the electron is ejected at very high speed
Alpha particle radiation occurs when
2 protons and 2 neutrons are ejected as 1 particle
Gamma radiation occurs when
the nucleus is in an excited state it can emit a “packet of energy” known as a photon. the number of protons and neutrons are NOT altered but instead the nucleus moves from a higher to a lower energy state
* most damaging
What protection is needed for alpha, beta, and gamma particles?
alpha: distance
Beta: distance & some shielding
Gamma: distance, lead shields, concrete walls
What is ionizing radiation?
IOnizing radiation is radiation with enough energy to remove tightly bound electrons from the atom’s orbits
causes the atom to become charged or ionized
can cause damage because it causes damage to DNA, RNA, proteins, and lipid
Lasers cannot produce
genetic mutations because they utilize non-ionizing heat (poses no threat to cellular DNA)
Lasers can cause
damage to the eyes because the light can be refracted to the back of the eye
Recommended yearly limits of radiation are
5,000 mrem to the torse
maximum dose to the fetus of a pregnant worker may not exceed 500 mrem over 9 month gestation
The greatest risk of rem exposure is
C-arm
How far should you stand to minimize the exposure of the C-arm or Xray machine?
6 feet
The intensity of any radiation is
intensity= 1/d^2
X-ray safety lies within 3 factors:
distance from the source, barriers (shielding) and exposure time
The photons of ionizing radiation have sufficient energy for
the separation of water molecules into positive and negative ions
The energy of laser photons is
insufficient for the production of ions
cannot produce genetic mutations b/c it is non-ionizing
Laser is
light amplification by stimulated emission of radiation
it is the light emitted when electrons jump from more distant orbital’s to orbital’s closer to the nucleus
Laser light is distinguished by
monochromatic (one wavelength, one color), coherent (waves are synchronous), collimated (focused into a narrow beam)
The three characteristics of lasers allow it to
generate intense light beams, deliver intense energy to a small target site, and send such beams efficiently and accurately through lenses
Primary mechanism of tissue interaction include:
photochemical (UV and blue end of visible)
thermal (all wavelengths)
There are two types of lasers:
continuous wave- power consistent
Pulsed: pause period allows for laser to emit high energy each pulse
Photochemical:
UV and visible wavelengths: photon absorption excites molecules which may react to form unwanted chemical products
Clinical lasers are used for
coagulation, cutting, and vaporization
Laser safety patient risk include
airway fire, bleeding, pneumo, and cuff failure from laser penetration
Personnel risk from laser injury include
laser injury, inhalation of surgical smoke
The maximum permissible exposure or MPE
determines level of eye/skin protection needed
Eye protection is of utmost importance with lasers because
the lens of the eye multiplies power density at the retina
retina is the location of photoreceptors
Eyewear must be labeled with
the rated wavelength and optical density (OD)
Wearers must ensure that eyewear
has sufficient OD at the laser’s wavelength
Optical density is
indicates inverse of amount of light transmitted by a material at that wavelength
means there is high absorbance
the higher the OD the less transmission and then we have to pick the proper wavelength
A laser’s minimum required OD is listed on laser’s warning sign
ensure eyewear OD is larger
Most healthcare laser systems are
class 4: hazardous to view beam, skin hazard and fire hazard
Reflections and lasers
specular (mirror like) reflections are more hazardous than diffuse reflections; keep shiny surfaces away from the field
How does biological damage occur?
o Electrons are released from atoms–>hit and bump into water molecules–>release free radicals–> unstable and damage DNA, RNA, proteins, and lipids–>Over a lifetime it can cause issues such as leukemia
Pressure relief valve:
if the pressure in the tube exceeds the valve pressure, then the valve is pushed up revealing vents through which pressure can be dissipated
ambu bag
Pressure reducing valve:
oxygen tank
Relationship between pressure, flow, and resistance
Flow= pressure/resistance
flowmeter: as flow increases, resistance decreases so pressure stays the same
Relationship between pressure, force, and surface area
Pressure= force/area
same force distributed over a smaller area leads to increased pressure
