Atomic Structures and Periodic Trends Flashcards
Nucleons
protons and neutrons
Atomic Number
number of protons in the nucleus of an atom
Mass Number
number of protons + number of neutrons
Isotopes
atoms of the same element differ in number of neutrons
Atomic Weight of an Element
weighted average of masses of its naturally occurring isotopes
Ion
charged atom
Anion
negatively charged ion
Cation
positively charged ion
Strong Nuclear fOrce
force holding protons and neutrons in a nucleus
Radioactive
nuclei are unstable
Radioactive Decay
transformation of an unstable nuclei to make them more stable
Parent
nucleus that undergoes radioactive decay
Daughter
more stable nucleus after radioactive decay
Alpha Particle
large nucleus wants to become more stable by reducing the number of protons and neutrons emits this
Alpha Particle Components
2 protons and 2 neutrons and travel short distances
Beta Decay
conversion of a neutron into a proton
Weak Nuclear Force
cause beta decay
Beta- Decay
unstable nucleus contains too many neutrons, convert a neutron into a proton and an electron, which gets ejected
Beta+ Decay
unstable nuclei contains too few neutrons, it converts a proton into a neutron and a positron, which is ejected
Electron Capture
unstable nucleus to increase number of neutrons by capturing electrons from closest electron shell to convert a proton into a neutron
Gamma Photons
electromagnetic radiation energy emitted after a nucleus in an excited energy state relaxes to ground state
Gamma Photons Mass
gamma photons have no mass or charge, so can penetrate matter most effectively
Half Life
time it takes for one-half of some sample of substance to decay
Nuclear Binding energy
energy released when individual nucleons were bound together by the strong force to form the nucleus. would also be equal to the energy required to break up the intact nucleus into individual nucleons.