# Table of Common Physical Constants 1

Series of different colored lasers. No matter the color, the speed of light is a constant. The speed of light is just one constant in this table of common constants. Credit: Pang Ka kit, Creative Commons

Here is a useful table of common constants. These physical constants appear time and again in chemistry and physics homework problems.

Why memorize them when you can just look them up.

I personally prefer to keep a sheet with these constants stuffed in the back of book. You can print up your own sheet with a PDF copy of the Table of Common Constants.

### TABLE OF COMMON CONSTANTS

 Name Symbol Value Speed of light c 299792458 m⋅s-1 Charge of an electron e 1.602176565(35)×10−19 C Universal gravitational constant G 6.67384(80)×10-11 N⋅m2/kg2 Planck’s constant h 6.626070040(81)×10−34 J⋅s h 4.135667662(25)×10−15 eV⋅s Dirac’s constant ħ 1.054571800(13)×10−34 J⋅s ħ 6.582119514(40)×10−16 eV⋅s Boltzmann’s constant k 1.3806488(13)×10−23 J⋅K-1 8.6173324(78)×10−5 eV⋅K-1 Avogadro’s constant NA 6.022140857(74)×1023 mol−1 Faraday’s constant F 96485.3365(21) C⋅mol−1 Ideal gas constant R 8.3144621(75) J⋅K−1⋅mol−1 Mass of an electron me 9.10938291(40)×10−31 kg 0.510998928(11) MeV/c2 Mass of a proton mp 1.672621777(74)×10−27 kg 938.272046(21) MeV/c2 Mass of a neutron mn 1.674927351(74)×10−27 kg 939.565378(21) MeV/c2 Atomic mass unit u, amu or Da 1.660538921(73)×10−27 kg 931.494061(21) MeV/c2 Permittivity of free space ε0 8.854187817×10−12 Coulomb’s constant 1/4πε0 8.9875517973681764×109 N⋅m2⋅C-2 Permeability of free space μ0 4π×10−7 N⋅A-2 Rydberg constant R∞ 1.0973731568539(55)×10−7 m-1 Bohr radius a0 5.2917721092(17)×10−11 m