CHAP. 14: DISPERSION SYSTEMS [CONTENTS] 466
Quantity Symbol, formula Value Note
Speed of light
in vacuum c 299792458 m s−^1 defined
Gas constant R 8.314472(15) J mol−^1 K−^1
Avogadro constant NA=L 6 .0221415(10)× 1023 mol−^1
Boltzmann constant k=kB=R/NA 1 .3806505(24)× 10 −^23 J K−^1
Elementary charge e 1 .60217653(14)× 10 −^19 C
Faraday constant F=eNA 96485.3383(83) C mol−^1
Planck constant h 6 .6260693(11)× 10 −^34 J s
Vacuum permeability μ 0 4 π× 10 −^7 J s^2 C−^2 m−^1 defined
Vacuum permittivity ε 0 = 1/(c^2 μ 0 ) 8. 8541878176.. .× 10 −^12 defined
Fine structure constant α=μ 0 e^2 c/(2h) 7 .297352568(24)× 10 −^3
Rydberg constant R∞=α^2 mec/(2h) 10973731.568525(73) m
Stephan-Boltzmann const. σ= 2π^5 k^4 /(15h^3 c^2 ) 5.67040(4)× 10 −^8 W m−^2 K−^4
Mass of electron
(atomic mass unit) me 9 .1093826(16)× 10 −^31 kg
Mass of proton mp 1 .67262171(29)× 10 −^27 kg
Unified atomic
mass unit u= 1 g mol−^1 /NA 1 .66053886(28)× 1027 kg
Bohr radius a 0 =ε 0 h^2 /(πmee^2 ) 0.5291772108(18)× 1010 m
Bohr magneton μB=eh/(4πme) 9 .27400949(80)× 10 −^24 J T−^1
Nuclear magneton μB=eh/(4πmp) 5 .05078343(43)× 10 −^27 J T−^1
Gravitational constant G 6 .6742(10)× 10 −^11 m^3 kg−^1 s−^2
Standard acceleration
of free fall g 9.80665 m s−^1 defined
Standard pressure pst 101.325 kPa or 100 kPa defined
Standard concentration cst 1 mol dm−^3 defined
Standard molality mst 1 mol kg−^3 defined
Temperature of
water triple point Ttr 273.16 K = 0.01◦C defined
