Electric Circuits, Solutions, Acids Bases and Buffers, pKa

Question 1

Define pKa

Answer 1

The pKa is the pH at which 50% of a weak acid or weak base is ionized and 50% is un-ionized

Question 2

T h e l o c a l a n e s t h e t i c s ar e p r e p a r e da s w h a t kindofsalts?

Answer 2

H y d r o c h l o r i d es a l t

Question 3

AreIocalanestheticwseakacidsor weak bases? Do theybecome more or less ionized as pH increases?

Answer 3

Localanesthetics are weak bases Local anesthetics become less ionized.(more un-ionized) as pH increases.

Question 4

Iflocal anesthetiics injectedinto anareaof localinfection,willtheonsetofactionbe h a s t e n e o d r s l o w e d W? h y

Answer 4

S p e e do f o n s e t w i l l b e s l o w e d b e c a u s e th e p r e v a i l i n g a c i d o s i s o f t h e i n f e c ted region increases extent
the of ionization,which slows diffusion
t h r o u g h l i p i d b i l a y e r s i , n c l u d i n g t h e l i p i d b i l a y e r o f n e u r o ns

Question 5

Whathappentsotheamounot fsaltthat dissolveisn waterwith increasingtempera- ture?Whathappentsotheamounot fgas thatdissolveisnliquidwithincreasingtem- perature?Whatprincipleapplies?

Answer 5

Thesolubilityof a saltincreasewsith increasingtemperatureM. oresalt dissolveisn waterwhentemperaturiencreasesT.hesolubiliryof a gas decreasewsith increasintgemperatureL.essgasdissolveisn waterwhen temperature increase. LeChatliers Principle

Question 6

TheOstwaldsolubilitycoefficienitsameas- ureofwhat?

Answer 6

It isameasureofthesolubilityofagasinafluid

Question 7

Whatisthedefinitionof theOstwaldsolu- bilitycoefficientW? hatisthesignificancoef theOstwaldsolubilitycoefficienitn anesthe- sia?

Answer 7

TheOstwaldsolubilitycoefficienist definedastheratioofthe concentra- tion ofgasdissolvedin solutionto theconcentratioonfgasin thegas phaseatequilibriumat37degreeCs.Blood/gapsartitioncoefficientfsor
i n h a l a t i o n aal n e s t h e t i casr e d e r i v e df r o m O s t w a l ds o l u b i l i t i e

Question 8

WhenNzOis turnedon,air bubblesexpand. W h o s el a w a p p l i e sa, n dw h y ?

Answer 8

Frck’slawofdiffusionappliesD. iffusionisproportionatol solubiliry. Fick’slawstatesin, part,moresorublgeasedsiffuseingreateqruantities; N2Ois34timesmoresolublein bloodthanNz.ThequantityofNzOdif_ fusingoutofthebloodintothebubbleisgreatetrhanthequantityofN2 diffusingfromthebubbleintotheblood

Question 9

Identifythetwolawsthatapplyto diffusion ofNzOandothergases

Answer 9

Fick’slawofdiffusionandGraham’lsaw

Question 10

G a s e ds i f f u s e d o w n a p a r t i a l p r e s s u r eg r a d ! entacrostsissuesuchasthealveolo_ capillarymembraneW. hatlawexplainsthis?

Answer 10

F i c k ‘ sl a w o f d i f f u s i on

Question 11

Fick’slawofdiffusionofagasacossa membranestatesthattherateofdiffusionis directlyproportionatlowhatthreefactors? Inverselyproportionatlowhattwofactors?

Answer 11

AccordingtoFick’slaw,theamounot fgasdiffusingisdirectlypropor_
3.
WhatisAvogadro’snumber?WhatisAvo- gadro’slaw?
Whatvolumewill 2 molesof gasoccupyat s t a n d a r dt e m p e r a t u r ( e0 d e g r e e Cs ) a n d pressur(e1atm)?Whoselawapplies?
Identift therelationshipthatexplainshow non-ideagl asebsehaveW. hatdoesthis relationshipsayaboutrealgases.
WhenNzOis turnedon,air bubblesexpand. W h o s el a w a p p l i e sa, n dw h y ?
Identifythetwolawsthatapplyto diffusion ofNzOandothergases.
G a s e ds i f f u s e d o w n a p a r t i a l p r e s s u r eg r a d ! entacrostsissuesuchasthealveolo_ capillarymembraneW. hatlawexplainsthis?
Thenumberofmoleculeisnonemoleofasubstance,6.02
x l0ri,isAvo_
gadro’snumberA. vogadrol’aswstatesthatonemoleofanideagl asoccu-
piesavolumeof22.4litersat1atmand0degreeCs.[WestR, espiratory P h y s i o l o g y1 , 9 9 0 p, l 6 4 l
44.8liters.Onemoleofagasatstandartdemperature
( 0 d e g r e e Cs ) a n d
standardpressur(el atm)occupieasvolumeof22,4L,so2moleswill
occupy44.8L,Avogadro’s
lawpermitsthiscalculation. parbrook
andKennyB, asicPhysicasndMeasuremeintAnaesthesi1a9,95, p54]
van derwaal’srelationshiepxplainhsownon-ideal
g a s e bs e h a v e T . h i s
relationshipholdsthatgasmoleculeosccupyvolumeandattractandrepel eachother.[Authors]
Frck’slawofdiffusionappliesD. iffusionisproportionatol solubiliry. Fick’slawstatesin, part,moresorublgeasedsiffuseingreateqruantities; N2Ois34timesmoresolublein bloodthanNz.ThequantityofNzOdif_ fusingoutofthebloodintothebubbleisgreatetrhanthequantityofN2 diffusingfromthebubbleintotheblood. parbrook
Whichgaslawexplainsdiffusionhypoxia?
10, Whoselawappliestothediffusionofgases Fick’slawofdiffusion.
l1
betweeangasphaseandaliquidphase?
DescribethesecondgaseffectW. hatlaw applies?
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RespiratorPy hysiology,
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W h e n o n e g a s d e l i v e r e da t a h i g h i n s p i r e d c o n c e n t r a t i o (n f i r s t g a s s u c h a s N 2 o ) a c c e l e r a t et hs e b l o o d u p t a k eo f a c o n c u r r e n t l ya d m i n i s t e r e dc o m -
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BasicPhysicasndMeasurement
tionalto:(t) thepartiapl ressurdeifference
of thegasacross
[Davis, andKennv. in Anaesthesi1a9,95p, 9l]
themem- brane(;2)theareaofthemembranea;nd(3)thesolubilityofthegasin
themembraneT. heamountof gasdiffusingis indirectlyproportionatlo:
(l) thethicknesosfthemembrane; (2)
and thesquarerootofthemolecu-
larweightofthegas

Question 12

G a s e st h a t a r e m o r e b l o o d s o l u b l ew i l l d i f - fuseacrossaliquid/gasinterfacesuchasthe a l v e o l a c r a p i l l a r ym e m b r a n i e n g r e a t e o r r lesseqruantitietshanalessolublegas? Whatlawapplies?

Answer 12

G a s e t sh a t a r e m o r e b l o o d s o l u b l ed i f f u s ei n g r e a t e qr u a n t i t i e as c r o s s Iiquid/gasinterfacesa,sdescribedbyFick’slawofdiifusion.

Question 13

Whichgaslawexplainsdiffusionhypoxia?

Answer 13

Ficks law of diffusion

Question 14

Whoselawappliestothediffusionofgases betweeangasphaseandaliquidphase

Answer 14

Ficks law of diffusion

Question 15

DescribethesecondgaseffectW. hatlaw applies?

Answer 15

W h e n o n e g a s d e l i v e r e da t a h i g h i n s p i r e d c o n c e n t r a t i o (n f i r s t g a s s u c h a s N 2 o ) a c c e l e r a t et hs e b l o o d u p t a k eo f a c o n c u r r e n t l ya d m i n i s t e r e d c ompanion gas (secondgassuchasisofluraneh,alothaned,esflurane,.,uofltt* rane,or enflurane)t,hisisthesecondgaseffect.Fick’slawofdiffusion explaintshisphenomen

Question 16

hathappensto thevolumeof thecuffof t h e e n d o t r a c h e at u l b e w h e n N z O i s t u r n e d on?ExplainthisphenomenoWn.hoselaw applies?

Answer 16

ThecuffwillexpandM. oreNzOwilldiffuseintothecufffromthesurface o f t h e t r a c h e a t h a n w i i l N z d i f f u s e f r o m t h e c u f f b e c a u s Ne z O i s m u c h moresolublein bloodthanNz.Fick’slawof diffusionapplie

Question 17

Whatlawexplainseachofthefollowing phenomenocno: ncentratioenffects,econd gaseffectd, iffusionhlpoxia?Explain.

Answer 17

F i c k ‘ s l a w o f d i f f u s i o n f o r g a s e e s x p l a i n t s h e s e p h e n o m e n Ea . a c h o f t h e s e phenomenoonccursbecausNezOismorebloodsolublethanNz.Accord- ingtoFick’slawofdiffusionforgasesth, egasthatismorebloodsoluble diffusesin greaterquantitiesfromalveoltiobloodandfrombloodto alveoli

Question 18

WhatdoesGraham’s law state?

Answer 18

G r a h a m ‘ lsa w s t a t e st h a t a g a sd i f f u s e sa t a r a t e t h a t i s i n v e r s e l yp r o p o r -
tionaltothesquarerootofitsmoleculawreigh

Question 19

G i v e a n e x a m p l oe f G r a h a m ‘ l sa w .

Answer 19

Graham’lsawstatetshattherateofdiffusionofagasisinverselpyropor- tionaltothesquarerootofitsmoleculawreightF. orexampleh,elium ([Ie)willdiffusefasterthanoxygen(O),whichwi]ldiffusefasterthan nitrousoxide(NzO

Question 20

WhatisHenrv’slaw?

Answer 20

Henry’slawstatesthattheamountofgasthatwilldissolveinsolutionisl proportionatol thepartiapl ressuroefthegasin contacwt iththesolution.

Question 21

Henry’s law is used for what two purposes?

Answer 21

Henry’slawisusedtocalculate(:1)theamountofoxygendissolvedin blood(Ozdissolve=dPOzx 0.003a) nd(2)theamounot f carbondioxide dissolveidn blood(COzdissolve=d0.067x PCOz

Question 22

Define and differentiate

between macroshock and microshock.

Answer 22

Macro shock refers to a large voltage applied to skin or tissue. Microshock refers to small voltages or currents applied directly to the heart.