Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
GES 332 Stars and Stellar Systems Nuclear Chemistry Notation A nucleus X contains a protons (Note that once you know a, you look up what symbol to use for X; i.e. a and X give the same information.), b neutrons and has c bound electrons. It is written as a+b +(a−c) a X The atomic number is a, the atomic mass or weight is a + b and the net electric charge is a − c. For example, a fully ionized Carbon-14 atom is written 14 +6 6 C while a singly ionized Helium-4 atom is written +1 4 2 He Again, note that we really don’t need to write the number of protons and the atomic symbol, so we will usually write the two atoms above as 14 +6 C and 4 He+1 Subatomic Particles Particle Charge (in units of electron charge) Mass (in kg) Symbol(s) electron positron (anti-electron) neutron proton anti-proton neutrino photon (gamma ray) alpha-particle -1 +1 0 +1 -1 0 0 +2 9 × 10−31 9 × 10−31 1.674 × 10−27 1.672 × 10−27 1.672 × 10−27 0 0 6.64 × 10−27 e− , β − e+ , β + n, n0 + p, p , H+ , 11 H+ p− νe , νµ , ντ γ, hν α, He2+ , 42 He2+