Constant

symbol

value

Speed of light in vacuo

c

2.997 924 58 x 108 m s−1

Planck constant

h

6.626 068 96 x 10−34 J s

Electric constant

ε0

8.854 187 817 x 10−12 F m−1

Magnetic constant

μ0

4π x 10−7 N A−2

Gravitational constant

G

 6.674 28 x 10−11 N m2 kg−2

Constant

symbol

value

Electronic charge

e

1.602 176 487 x 10−19 C

Bohr magneton

μB

927.400 915 x 10−26 J T−1

Nuclear magneton

μN

5.050 783 24 x 10-27 J T−1

Constant

symbol

value

Fine structure constant

α

7.297 352 5376 x 10−3

Electron mass

me

9.109 382 15 x 10−31 kg

Proton mass

mp

1.672 621 637 x 10−27 kg

Neutron mass

mn

1.674 927 211 x 10−27 kg

Atomic mass unit

u

1.660 538 782 x 10−27 kg

Rydberg constant

R∞

10 973 731.568 527 m−1

Bohr radius

a0

0.529 177 208 59 x 10−10 m

Hartree energy

Eh

4.359 743 94 x 10−18 J

Electron g factor

g

−2.002 319 304 3622

Constant

symbol

value

Atomic mass unit

u

1.660 538 782 x 10−27 kg

Avogadro constant

L or NA

6.022 141 79 x 1023 mol−1

Boltzmann constant

k

1.380 6504 x 10−23 J K−1

Gas constant

R

8.314 472 J mol−1 K−1

Faraday constant

F

96 485.3399 C mol−1

Stefan-Boltzmann constant

σ

5.670 400 x 10−8 W m−2 K−4

Constant

symbol

value

Acceleration due to gravity

g

9.806 65 m s−2

Mean radius of earth

6371 km

Mean density of earth

5517 kg m−3

Length of year

365.256 day

Standard atmosphere

 atm

101 325 Pa