Physico-chemical constants

Avogadro, Boltzmann, the gas constant, Faraday, black-body radiation and the molar quantities chemists use.

N_A

Avogadro constant 6.022 140 76 × 10²³ mol⁻¹ Physico-chemical exact

k

Boltzmann constant 1.380 649 × 10⁻²³ J K⁻¹ Physico-chemical exact

F

Faraday constant 96 485.332 12… C mol⁻¹ Physico-chemical exact

R

Gas constant 8.314 462 618… J mol⁻¹ K⁻¹ Physico-chemical exact

σ

Stefan–Boltzmann 5.670 374 419… × 10⁻⁸ W m⁻² K⁻⁴ Physico-chemical exact

b

Wien constant 2.897 771 955… × 10⁻³ m K

All 25 values

Symbol	Quantity	Value (uncertainty)	Unit	Rel. unc.
$m_{u}$	Atomic mass constant	1.660 539 068 92(52) × 10⁻²⁷	kg	3.1 × 10⁻¹⁰
$m_{u} c^{2}$	Atomic mass constant energy equivalent	1.492 418 087 68(46) × 10⁻¹⁰	J	3.1 × 10⁻¹⁰
$m_{u} c^{2}$	Atomic mass constant energy equivalent in MeV	931.494 103 72(29)	MeV	3.1 × 10⁻¹⁰
$N_A$	Avogadro constant	6.022 140 76 × 10²³	mol⁻¹	exact
$k$	Boltzmann constant	1.380 649 × 10⁻²³	J K⁻¹	exact
$k$	Boltzmann constant in eV/K	8.617 333 262… × 10⁻⁵	eV K⁻¹	exact
$k/h$	Boltzmann constant in Hz/K	2.083 661 912… × 10¹⁰	Hz K⁻¹	exact
$k/hc$	Boltzmann constant in inverse meter per kelvin	69.503 480 04…	m⁻¹ K⁻¹	exact
$F$	Faraday constant	96 485.332 12…	C mol⁻¹	exact
$c_{1}$	First radiation constant	3.741 771 852… × 10⁻¹⁶	W m²	exact
$c_1L$	First radiation constant for spectral radiance	1.191 042 972… × 10⁻¹⁶	W m² sr⁻¹	exact
$n_{0}$	Loschmidt constant (273.15 K, 100 kPa)	2.651 645 804… × 10²⁵	m⁻³	exact
$n_{0}$	Loschmidt constant (273.15 K, 101.325 kPa)	2.686 780 111… × 10²⁵	m⁻³	exact
$R$	Molar gas constant	8.314 462 618…	J mol⁻¹ K⁻¹	exact
$M_{u}$	Molar mass constant	1.000 000 001 05(31) × 10⁻³	kg mol⁻¹	3.1 × 10⁻¹⁰
$M(¹²C)$	Molar mass of carbon-12	12.000 000 0126(37) × 10⁻³	kg mol⁻¹	3.1 × 10⁻¹⁰
$N_Ah$	Molar Planck constant	3.990 312 712… × 10⁻¹⁰	J Hz⁻¹ mol⁻¹	exact
$V_{m}$	Molar volume of ideal gas (273.15 K, 100 kPa)	22.710 954 64… × 10⁻³	m³ mol⁻¹	exact
$V_{m}$	Molar volume of ideal gas (273.15 K, 101.325 kPa)	22.413 969 54… × 10⁻³	m³ mol⁻¹	exact
$S₀/R$	Sackur-Tetrode constant (1 K, 100 kPa)	−1.151 707 534 96(47)		4.1 × 10⁻¹⁰
$S₀/R$	Sackur-Tetrode constant (1 K, 101.325 kPa)	−1.164 870 521 49(47)		4.0 × 10⁻¹⁰
$c_{2}$	Second radiation constant	1.438 776 877… × 10⁻²	m K	exact
$σ$	Stefan-Boltzmann constant	5.670 374 419… × 10⁻⁸	W m⁻² K⁻⁴	exact
$b^{'}$	Wien frequency displacement law constant	5.878 925 757… × 10¹⁰	Hz K⁻¹	exact
$b$	Wien wavelength displacement law constant	2.897 771 955… × 10⁻³	m K	exact