**Constant** | **Symbol** | **Value** |

acceleration due to gravity | g | 9.8 m s^{-2} |

atomic mass unit | amu, m_{u} or u | 1.66 x10^{-27} kg |

Avogadro's Number | N | 6.022 x 10^{23} mol^{-1} |

Bohr radius | a_{0} | 0.529 x 10^{-10} m |

Boltzmann constant | k | 1.38 x 10^{-23} J K^{-1} |

electron charge to mass ratio | -e/m_{e} | -1.7588 x 10^{11} C kg^{-1} |

electron classical radius | r_{e} | 2.818 x 10^{-15} m |

electron mass energy (J) | m_{e}c^{2} | 8.187 x 10^{-14} J |

electron mass energy (MeV) | m_{e}c^{2} | 0.511 MeV |

electron rest mass | m_{e} | 9.109 x 10^{-31} kg |

Faraday constant | F | 9.649 x 10^{4} C mol^{-1} |

fine-structure constant | α | 7.297 x 10^{-3} |

gas constant | R | 8.314 J mol^{-1} K^{-1} |

gravitational constant | G | 6.67 x 10^{-11} Nm^{2}kg^{-2} |

neutron mass energy (J) | m_{n}c^{2} | 1.505 x 10^{-10} J |

neutron mass energy (MeV) | m_{n}c^{2} | 939.565 MeV |

neutron rest mass | m_{n} | 1.675 x 10^{-27} kg |

neutron-electron mass ratio | m_{n}/m_{e} | 1838.68 |

neutron-proton mass ratio | m_{n}/m_{p} | 1.0014 |

permeability of a vacuum | μ_{0} | 4π x 10^{-7} N A^{-2} |

permittivity of a vacuum | ε_{0} | 8.854 x 10^{-12} F m^{-1} |

Planck constant | h | 6.626 x 10^{-34} J s |

proton mass energy (J) | m_{p}c^{2} | 1.503 x 10^{-10} J |

proton mass energy (MeV) | m_{p}c^{2} | 938.272 MeV |

proton rest mass | m_{p} | 1.6726 x 10^{-27} kg |

proton-electron mass ratio | m_{p}/m_{e} | 1836.15 |

Rydberg constant | r_{∞} | 1.0974 x 10^{7} m^{-1} |

speed of light in vacuum | C | 2.9979 x 10^{8} m/s |