Physical Chemistry Essentials - Hofmann A. 2018
Physico-chemical Data and Resources
1.3 Units and Constants
1.3.1 Decimal Factors
Table 1.2
Decimal factors
Factor |
Prefix |
Symbol |
Factor |
Prefix |
Symbol |
10−1 |
deci |
d |
10 |
deka |
da |
10−2 |
centi |
c |
102 |
hekto |
h |
10−3 |
milli |
m |
103 |
kilo |
k |
10−6 |
micro |
m |
106 |
mega |
M |
10−9 |
nano |
n |
109 |
giga |
G |
10−12 |
pico |
p |
1012 |
tera |
T |
10−15 |
femto |
f |
1015 |
peta |
P |
10−18 |
atto |
a |
1018 |
exa |
E |
1.3.2 The Greek Alphabet
Table 1.3
The Greek alphabet
Α, α |
alpha |
Ι, ι |
iota |
Σ, σ |
sigma |
Β, β |
beta |
Κ, κ |
kappa |
Τ, τ |
tau |
Γ, γ |
gamma |
Λ, λ |
lambda |
Y, υ |
upsilon |
Δ, δ |
delta |
Μ, μ |
mu |
Φ, ϕ |
phi |
Ε, ε |
epsilon |
Ν, ν |
nu |
Χ, χ |
chi |
Ζ, ζ |
zeta |
Ξ, ξ |
xi |
Ψ, ψ |
psi |
Η, η |
eta |
Π, π |
pi |
Ω, ω |
omega |
Θ, θ |
theta |
Ρ, ρ |
rho |
1.3.3 SI Base Parameters and Units
Table 1.4
SI base parameters and units
Symbol |
Parameter |
Unit |
Name |
I |
Electric current |
1 A |
ampere |
I v |
Light intensity |
1 cd |
candela |
l |
Length |
1 m |
metre |
m |
Mass |
1 kg |
kilogram |
n |
Molar amount |
1 mol |
mole |
t |
Time |
1 s |
second |
T |
Temperature |
1 K |
kelvin |
1.3.4 Important Physico-chemical Parameters and Units
Table 1.5
Important physico-chemical parameters and units
Symbol |
Parameter |
Unit |
Name |
b |
Molality |
1 mol kg−1 |
|
B |
Magnetic induction |
1 T = 1 kg s−2 A−1 = 1 V s m−2 |
tesla |
c |
Molar concentration |
1 mol l−1 |
|
C |
Electric capacitance |
1 F = 1 kg−1 m−2 s4 A2 = 1 A s V−1 |
farad |
E |
Energy |
1 J = 1 kg m2 s−2 = 1 C V |
joule |
ε |
Molar extinction coefficient |
1 l mol−1 cm−1 |
|
ε |
Permittivity |
1 F m−1 |
|
F |
Force |
1 N = 1 kg m s−2 = 1 J m−1 |
newton |
F |
Magnetic flux |
1 Wb = 1 kg m2 s−2 A−1 = 1 V s |
weber |
G |
Electric conductance |
1 S = 1 kg−1 m−2 s3 A2 = 1 Ω−1 |
siemens |
H |
Enthalpy |
1 J = 1 kg m2 s−2 |
joule |
η |
Viscosity |
1 P = 0.1 kg m−1 s−1 = 0.1 Pa s |
poise |
i |
Current density |
1 A m−2 |
|
j |
Flux density |
1 mol m−2 s−1 |
|
κ |
Conductivity |
1 S m−2 |
|
L |
Magnetic inductivity |
1 H = 1 kg m2 s−2 A−2 = 1 V A−1 s |
henry |
Λm |
Molar conductivity |
1 S m2 mol−1 |
|
M |
Molar mass1 |
1 g mol−1 = 1 Da |
(dalton) |
μ |
Electric dipole moment |
1 D = 3.336·10−30 C m |
debye |
ν |
Frequency |
1 Hz = 1 s−1 |
hertz |
p |
Pressure |
1 Pa = 1 kg m−1 s−2 = 1 N m−2 |
pascal |
P |
Power |
1 W = 1 kg m2 s−3 = 1 J s−1 |
watt |
Q |
Electric charge |
1 C = 1 A s |
coulomb |
ρ |
Density |
1 g cm−3 |
|
ρ* |
Mass concentration |
1 mg ml−1 |
|
R |
Electric resistance |
1 Ω = 1 kg m2 s−3 A−2 = 1 V A−1 |
ohm |
S |
Entropy |
1 J K−1 |
|
θ |
Temperature |
1 °C |
degree Celsius |
u |
Ion mobility |
1 m2 s−1 V−1 |
|
U, ϕ, E |
Electric potential (voltage) |
1 V = 1 kg m2 s−3 A−1 = 1 J A−1 s−1 |
volt |
V |
Volume |
1 l = 1 dm3 |
|
V m |
Molar volume |
1 l mol−1 |
|
v |
Partial specific volume |
1 ml g−1 |
|
w |
Mass fraction Volume fraction |
1 (typically given in %w/w, %w/v or %v/v) |
|
x |
Mole fraction |
1 |
|
z |
Charge number |
1 |
1Note that the molecular mass is the mass of one molecule given in atomic mass units (u, Da). The molar mass is the mass of 1 mol of molecules and thus has the units of g mol−1
1.3.5 Important Physico-chemical Constants
Table 1.6
Important physico-chemical constants
Symbol |
Constant |
Value |
c |
Speed of light in vacuo |
2.99792458·108 m s−1 |
e |
Elementary charge |
1.6021892·10−19 C |
ε0 = (μ0·c2)−1 |
Permittivity in vacuo |
8.85418782·10−12 A2 s4 m−3 kg−1 |
F = e·NA |
Faraday’s constant |
9.648456·104 C mol−1 |
g |
Earth’s gravity near surface |
9.81 m s−2 |
ge = 2 μe/μB |
Landé factor of free electron |
2.0023193134 |
γp |
Gyromagnetic ratio of proton |
2.6751987·108 s−1 T−1 |
h |
Planck’s constant |
6.626176·10−34 J s |
kB = R/NA |
Boltzmann’s constant |
1.380662·10−23 J K−1 |
me |
Mass of electron |
9.109534·10−31 kg |
mn |
Mass of neutron |
1.6749543·10−27 kg |
mp |
Mass of proton |
1.6726485·10−27 kg |
μ0 |
Magnetic field constant |
4π·10−7 m kg s−2 A−2 |
μΒ = e·h/(4π·me) |
Bohr magneton |
9.274078·10−24 J T−1 |
με |
Magnetic moment of electron |
9.284832·10−24 J T−1 |
μΝ = e·h/(4π·mp) |
Nuclear magneton |
5.050824·10−27 J T−1 |
NA, L |
Avogadro’s (Loschmidt’s) constant |
6.022045·1023 mol−1 |
pø |
Standard pressure (IUPAC) |
1.00·105 Pa |
pnormal |
Normal pressure (NIST) |
1 atm = 1013.25 hPa |
R |
Gas constant |
8.31441 J K−1 mol−1 |
R∞ |
Rydberg’s constant |
1.097373177·107 m−1 |
Tø, θø |
Standard temperature (IUPAC) |
273.15 K, 0 °C |
Tnormal, θnormal |
Normal temperature |
298.15 K, 25 °C |
u |
Atomic mass unit |
1.6605402·10−27 kg |
Vm ø = R·Tø/pø |
Molar volume of an ideal gas |
22.41383 l mol−1 |
1.3.6 Conversion Factors
Table 1.7
Conversion factors for energy
J |
cal |
eV |
|
1 J |
1 |
0.2390 |
6.24150974·1018 |
1 cal |
4.184 |
1 |
2.612·1019 |
1 eV |
1.60217646·10−19 |
3.829·10−20 |
1 |
Table 1.8
Conversion factors for pressure
Pa |
bar |
atm |
mm Hg (Torr) |
psi |
|
1 Pa |
1 |
10−5 |
9.869·10−6 |
7.501·10−3 |
1.450·10−4 |
1 bar |
105 |
1 |
0.9869 |
750.1 |
14.50 |
1 atm |
1.013·105 |
1.013 |
1 |
760.0 |
14.69 |
1 mm Hg (Torr) |
133.3 |
1.333·10−3 |
1.316·10−3 |
1 |
1.933·10−2 |
1 psi |
6.895·104 |
6.897 10−2 |
6.807 10−2 |
51.72 |
1 |
1.3.7 Thermodynamic Properties of Select Substances
Table 1.9
Enthalpy of formation, Gibbs free energy of formation and molar heat capacity of select substances at normal conditions (Tnormal = 298 K, pnormal = 1.013 bar)
Species |
ΔH f in kJ mol−1 |
ΔG f in kJ mol−1 |
C p,m in J K−1 mol−1 |
C(graphite) |
0 |
0 |
8.53 |
HCO3 − (aq) |
−689.9 |
−586.8 |
|
H2(g) |
0 |
0 |
28.82 |
H+ (aq) |
0 |
||
H2O(l) |
−285.83 |
−237.14 |
75.4 |
H2O(g) |
−241.83 |
−228.61 |
33.58 |
Ni(OH)2(s) |
−444 |
||
O2(g) |
0 |
0 |
29.35 |
O3(g) |
142.67 |
163.19 |
39.22 |
OH− (aq) |
−230.02 |
−157.22 |