Equilibrium Study Cheat Sheet

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EQUILIBRIUM

state IS reached when [reactants] & [products] ( constant over time

eq mixture

reacs & prods

start 3 NO2

14.1 Eq State

N2O4

N2O4C9)

2NO(9)

many rxns acc dont go to completion

[]

NO2

all chen rxas are reversible

time

"Irreversible"- proceed rearly to completion

reverse rxns too slow to b detected

SAMPLE rate = Kr [N2O4] rater = K, [NO2]

rater

N2O4

2NO2

dynamic eg: forward & rev rxn continue @ equal rates

chem en

1

N2O4

2No2

(M)

cate

rater

more [NO2],

rate of exnr

14.2 Eq Constant

law ofmass action

Kc= = [C]°CD]"

products

eg expression rxn order based on stach coe fficients

[A]°[B]"

reacs

dont

need

substance in eq. constant expression must not be 80/12/119

Units

L)eq equation @ 1 temp always has the same value

=

Kc=

CA]a[B]b

reverse

ГХЛ

=

[c]'[D]' CD]"

Kc & Kg' diff

specify СХЛ

adding rxns: aA

bB

Kc, = CBP

bB

CC

Cc]c

Kc2 =

KcI X Kc2

CO75

[c]c

[C]

11

X

=

Kcoverall

aA

Y

kc overall

[A]a

CAJa

IBJb

14.3 Eq Constant Kp

partial pressure: pressure tht I gas exerts

Kp writing eq equations IN terms of P rather then

C

good for gases

ratios of partial P In atnos (atm)

units cancel

Kp& Kc relate aA +bB

cC + dD

PA = nA RT

NA

PA=

A=

>

RT = [A]RT

[c]' [0]

(ctd)-(atb)

kp=

"

x RT

OR

Kp = Kc(RT)an

R= O. 08206

C.ata

nol.k

[A Ja [B]b