5 Steps to a 5 AP Chemistry 2019

Exam Resources ❮ 397

DG° = DH° - TDS°

= - RT in K = - 2.303 RT log K

= - nFE°

DG = DG° + RT ln Q = DG° + 2.303 RT log Q

q = mcDT

Cp = DH/DT

Light and Electrons

E = energy n = frequency l = wavelength

p = momentum v = velocity n = principal quantum number

m = mass E = hn c = ln

En = (-2.178 × 10 -^18 /n^2 )J

Speed of light, c = 3.0 × 108 ms-^1

Planck’s constant, h = 6.63 × 10 -^34 Js

Solutions

Molarity, M = moles solute per liter solution

Kinetics

ln[A ]t - ln[A ]o = -kt

kt

1

[A]

1

to[A]

−=

=

− 







k +

E

RT

ln

1

a ln A

Ea = activation energy

k = rate constant

A = frequency factor

t1/2 = 0.693/k

Electrochemistry

I = current (amperes) q = charge (coulombs)

E° = standard reduction potential K = equilibrium constant

Faraday’s constant, F = 96,500 coulombs per mole of electrons

==

°

Iqt

nE

/log

0.0592

K

Equilibrium

Q = reaction quotient

Q

[C][D]

[A][B]

,whereaA bB cC dD

cd

=+ab  +

equilibrium constants:

Ka (weak acid) Kb (weak base) Kw (water)

Kp (gas pressure) Kc (molar concentrations)

KK K

[H ][A]

[HA]

[OH][HB]

[B]

(P)(P)

ab p (P)(P)

c

c

d

d

a

a

b

== = b

+− −+

22-Moore_APP_p371-412.indd 397 31/05/18 2:00 pm