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Chemistry Physics Notes
7/7 & 14

Symbols P=pressure V=volume T= temp

STD= standard temp and pressure, which means 0 K & 760mmHg occurs at sea level. As increase distance from sea level -> chg in PaP occur, therefore anesthesia is delivered differently depending on the Atm pr. They will give us a formula for this later.

PaP = partial pressure

weight- gm, mg mcg
Volume- liter, ml
Length meter

T is a way of measuring the average kinetic energy of the molecules in a substance, or the average kinetic velocity of molecules, it is work or movt.

Potential energy is stored energy which is ready to produce work

Scales of temp F, C, K

C=5/9(F-32) F=9/5(c)+32 K=C+273

Matter can be broken down into elements building blocks

Elemental building blocks atoms

Atomic # - A# - corresponds to # of protons in nuc

Atomic wt-AW- mass of atom in terms of the weight of the neutrons and protons in grams. Es weight not counted because of bonding and their too light anyway

Oxygens A#=8 (protons) AW=16(protons & neutrons)

Avagadros # - 6.02 X 10 23rd molecules are present , but the A# & AW will vary because the weight of each different atom varies

Conversion 1ATM = 760mmHg = 14.07PSI

1 mmHg = 1.36 or 1.4 Cm H2O

Bohr Model looks at reactivity,

- Theory of octets

- Valence (outer most shell) strives for stability by trying to achieve

noble gas configuration

Li One e donated so configuration goes to He -> Li+

K donates one e so the configuration goes to Ar, -> K+

C has 4 valence es so depending on what C reacts with determines whether es are donated or accepted (kind of bond)

N-5VE O- 6VE F 7VE


Na 1 e -> Na+

Polar molecule has a + and end, and e hangs more toward one

end of the molecule than the other. The distance from

electron to nucleus in not equidistant

Non Polar es are equidistant between nuclei because there are

no neg or+ forces pulling e to one side or the other

Univalent bonding- + valence # means atom donates e, and the

accepting atom is called a negative valence

Na+ Cl- refer to the valence of the atom

Isotopes are elements with different AW

Like C12 & C14. Isotopes react with elements with some differences

Cohesion RT kinetic nrg and state of matter

Adhesion similar concept but the molec are not alike?

Gas laws abbr IG=ideal gas

RG=real gas

PV=nRT formula

P=pressure, V=volume, n=#moles, R=gas constant, T=temp

B=Boyles law






Gas laws work for ideal gasses only, and is theoretical. The molecules considered are far apart and have no attraction

Rare gasses exist only in the lab and have negligible cohesiveness

They behave like Ig(ne, AR) when for eg (inc T & dec P)



P = The force exerted on a cylinder side wall

Collisions occur inside the cylinder

The inc P causes inc collisions

Dec P causes dec collisions

Pressure is measured by means of measuring a column of liquid (Hg or

H2O) in which the level of the column of liquid is maintained

In reducing the V of a gas (compressing it) means P is inc but T remains constant

All gas laws are different variations of the IG laws

Grahams Law-

- diffusion rate = 1/ mw sq root of mw, dont forget radical sign

- when gasses are liberated, they dispense quickly in order to fill the space

that are occupying, think of trying to achieve = pressures in both areas


Daltons law - the total pressure exerted is = to the pressure of all the gasses in the mixture.

If vapor pressure - (VP) of isoforane is 239, then figure its PaP when mixed in 100% O2. 100% = 1.0 x 760 = 760 - (239) = 521 = 68.5% O2 is mixed with isoforane

VPT - can stay constant - we are looking at the % of what gas exerts what pressure in a container. Then add the sums of all the pressures that are exerted

VP is the pressure necessary to keep the mixture in liquid state( liquid readily wants to go the gasseous state

Gas changes - Triangle G C=T&V at const P

T P G=T&P at const V

C V B B=V&P at const T

B - at constant T, P&V vary inversely - P1V!=P2V2

Eg 400mg x 8L = 1600 mg x y, y = 2L, notice the proportionality of the #'s

C - T&V at constant P, V directly prop to T in Kelvin at const P

T1( 9) T2 (x) T2 = 54

G - P directly prop to T is V is constant, PV = nRT, as gas is released form a cylinder of compressed gas, then pressure inside will gradually dec and will be indicated on gauge ( think of moles of gas being released)

Bourdon gauge - measures hi pressure in cylinder

LaPlaces law - tension may be defined a sthe internal force generated by a structure - for Cylinders - T = Pr where P- pr of fld in cyl, r- radius, T-tension

blood vs - the tension in the wall is proportional to the

radius, therefore the larger the radius, the

higher the tension , and the > likely the vs is to


heart - > filling pressure = > tension in the ventricular

wall, which is related to Starling & preload

Spheres - T = (Pr) / 2

Alveoli - with surfactant open and round,

collapsed with out surfactant -

Critical Temp is associated with compressed gasses

- gasses will liquefy if sufficient pr is applied and T is below the critical


Joule-Thompson effect-

Avagadro's Law - one mol of any gas at some temp has the same # of molecules( but probably wont weigh the same)

Gram Molecular Weight- is the weight of 1 mol of a substance

Diffusion - VanDer Waals forces

Ficks Law of Diffusion - a gas always diffuses from an area of > pr to area of

< pr


rate of diffusion = P1-P2(area)(soluability) / (memb thickness) (sq rt mw)

the diff rate is directly proportional to the Pa P gradient, the area of the membrane its passing thru, and the soluability of the gas that is diffusing thru the membrane

Baricity deals with density of the local anes used in spinals and deals with diffusion 1. Isobaric soln - of local anes has the same baricity as CSF so it stays 

where you put it

2. hypotonic - lighter than CSF so it will go up

3. hyperbaric - heavier than CSF so it will go down

1,2 are usually used

Density = M / V Gas Density = GM wt / GM vol

GMV = Molec wt of the gas / wt of gas per liter


Know Vapor

    1. gas goes through vaporizer
    2. picks up anes gasses
    3. how this affect changing dial
    4. quickest way to get anesthesia gasses to pt
    5. inc flow thru so deliver more flow thru
    6. dial gives what % delivery of what gas
    7. know vapor pressure, 100% O2,
    8. del anes in denver is different than here - why?
    9. Understand the theory of gas laws
    10. Know concepts of why inhalants work
    11. Bernoulis iffect
    12. Inc IV guage from 22-18 change diameter and inc vol bu 4 in the same amt of time


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