Nuclear Physics Flashcards
Work
a force acting through a distance
force
any action on an object that can cause the object to change speed or direction
energy
the ability to do work
5 forms of energy
Kinetic Energy (KE)
Potential Energy (PE)
Thermal Energy (TE)
Chemical Energy (CE)
Electrical Energy (EE)
anything that has mass and takes up space
matter
Solid, Liquid, Gas (vapor)
3 phases of matter
anything that takes up space and has a charge
mass
positively charged (+)
1.00727 amu
at the nucleus
the number of ______ determines the element
protons
neutrally charged (0)
1.00866 amu
at the nucleus
determines the isotope of an element
neutrons
negatively charged (-)
0.000548 amu
makes up the cloud/rings/volume
the outer most shell determines the chemical behavior or properties of an atom
electron
atomic number
the number of protons
mass
the number of protons plus neutrons
Nuclide Notation:
X
Z
A
x = symbol for element
z = atomic number: number of protons
A = Mass number: number of protons (Z) plus number of neutrons (N)
periods
rows on the periodic table that tells us how many energy shells
groups
columns that tells us the number of valence electrons and how the element will be have chemically and have similar chemical properties
only has two electrons
k-shell
neutrons and protons
constituent particle of the atomic nucleus
nucleon
atom characterized by the constitution of its nucleus, which is specified by a combination of protons and neutrons
Nuclide
nuclides which have the same number of protons but different numbers of neutrons
Isotope
nuclides which have the same number of protons but different numbers of neutrons
isotope
E = mc^2
Mass-Energy Equivalence Formula
mass and energy are interchangeable
Mass-Energy Equivalence Formula
Pair Annihilation
where a positron and an negatron collide and are transformed into two photons of electromagnetic energy 0.511MeV
mass defect
total mass of the atom is less than the sum of the masses of the individual protons and neutrons
binding energy
the energy equivalent of mass defect
if the total binding energy of a nucleus is divided by the total number of nucleons in the nucleus
very weak attractive force between all nucleons
relatively long range
gravitational force
strong repulsive force between like particles (protons)
relatively long range
electrostatic force
strong attractive force between all nucleons
extremely short range
nuclear force
When an atom is radioactive it will change its nuclear configuration by eliminating surplus nucleons through transformations. This is done by changing neutrons to protons, or vice versa, and then ejecting the surplus mass or energy from the nucleus.
Radiation
the property of certain nuclides to spontaneously emit radiation
radioactivity
radioactive decay
process by which a nucleus spontaneously disintegrates (or is transformed) by one or more discrete energy steps until a stable state is reached
parent
the nucleus before the decay
daughter
the nucleus after the decay
decay chain
the various steps from parent to daughter are traced to stability, a series of transmutations is seen
a complete chain includes the original parent, all of its daughters, and the final stable, end-product
when the parent activity equals the daughter activity at the same time
radioactive equilibrium
a nucleus in an excited state (higher energy level) but has the same atomic number and mass number
isomer
isomeric transition
occurs immediately after particle emission; however the nucleus may remain in an excited state for a measurable period of time before dropping to the ground state at its own characteristic rate
curie
a unit of radioactivity, corresponding to 3.7x 10^10 dps (disintegration per second) 2.22 x 10^12 dpm (disintegration per minute)
