Quantity
Symbol
Value1 (SI units)
Relative Standard Uncertainty
atomic mass constant (unified atomic mass unit)
m
u
=
1
u
{\displaystyle m_{u}=1\ u\,}
1.660 538 86(28) × 10-27 kg
1.7 × 10-7
Avogadro's number
N
A
,
L
{\displaystyle N_{A},L\,}
6.0221417(10) × 1023
1.7 × 10-7
Boltzmann constant
k
=
R
/
N
A
{\displaystyle k=R/N_{A}\,}
1.380 6505(24) × 10-23 J·K-1
1.8 × 10-6
Faraday constant
F
=
N
A
e
{\displaystyle F=N_{A}e\,}
96 485.3383(83)C·mol-1
8.6 × 10-8
first radiation constant
c
1
=
2
π
h
c
2
{\displaystyle c_{1}=2\pi hc^{2}\,}
3.741 771 38(64) × 10-16 W·m2
1.7 × 10-7
for spectral radiance
c
1
L
{\displaystyle c_{1L}\,}
1.191 042 82(20) × 10-16 W · m2 sr-1
1.7 × 10-7
Loschmidt constant
at
T
{\displaystyle T}
=273.15 K and
p
{\displaystyle p}
=101.325 kPa
n
0
=
N
A
/
V
m
{\displaystyle n_{0}=N_{A}/V_{m}\,}
2.686 7773(47) × 1025 m-3
1.8 × 10-6
gas constant
R
{\displaystyle R\,}
8.314 472(15) J·K-1 ·mol-1
1.7 × 10-6
molar Planck constant
N
A
h
{\displaystyle N_{A}h\,}
3.990 312 716(27) × 10-10 J · s · mol-1
6.7 × 10-9
molar volume of an ideal gas
at
T
{\displaystyle T}
=273.15 K and
p
{\displaystyle p}
=100 kPa
V
m
=
R
T
/
p
{\displaystyle V_{m}=RT/p\,}
22.710 981(40) × 10-3 m3 ·mol-1
1.7 × 10-6
at
T
{\displaystyle T}
=273.15 K and
p
{\displaystyle p}
=101.325 kPa
22.413 996(39) × 10-3 m3 ·mol-1
1.7 × 10-6
Sackur-Tetrode constant
at
T
{\displaystyle T}
=1 K and
p
{\displaystyle p}
=100 kPa
S
0
/
R
=
5
2
{\displaystyle S_{0}/R={\frac {5}{2}}}
+
ln
[
(
2
π
m
u
k
T
/
h
2
)
3
/
2
k
T
/
p
]
{\displaystyle +\ln \left[(2\pi m_{u}kT/h^{2})^{3/2}kT/p\right]}
-1.151 7047(44)
3.8 × 10-6
at
T
{\displaystyle T}
=1 K and
p
{\displaystyle p}
=101.325 kPa
-1.164 8677(44)
3.8 × 10-6
second radiation constant
c
2
=
h
c
/
k
{\displaystyle c_{2}=hc/k\,}
1.438 7752(25) × 10-2 m·K
1.7 × 10-6
Stefan-Boltzmann constant
σ
=
(
π
2
/
60
)
k
4
/
ℏ
3
c
2
{\displaystyle \sigma =(\pi ^{2}/60)k^{4}/\hbar ^{3}c^{2}}
5.670 400(40) × 10-8 W·m-2 ·K-4
7.0 × 10-6
Wien displacement law constant
b
=
(
h
c
/
k
)
/
{\displaystyle b=(hc/k)/\,}
4.965 114 231...
2.897 7685(51) × 10-3 m · K
1.7 × 10-6