this spontaneously emits particles and energy and transforms itself into another atom to reach stability

: also known as radioactive decay

any nuclei that undergo radioactive decay (this is also one type of radioisotope)

Isotopes that are unstable by either having too few or too many neutrons

- May originate at the time of the Earth's formation and are still decaying very slowly - May also be produced in the upper atmosphere through cosmic radiation

- Man-made products artificially produced in machines such as particle accelerators or nuclear reactors.

- occurs in a neutron-rich nuclei - Occurs in stable nuclides bombarded with neutrons in nuclear reactors

is created in the nucleus and is ejected with considerable kinetic energy and escapes the atom

conversion that also occurs during beta emission

increases by one (Z = Z + 1), while the atomic mass number remains the same (A = constant)

emitted during beta emission absorbed by aluminum

- Important for some nuclear medicine imaging. - Occurs in proton-rich nuclei. - Occurs in stable nuclei bombarded with charged particles in cyclotron

conversion that also occurs during positron emission

decrease to the atomic number by 1 (2 = Z - 1) while the atomic mass number remains the same (A = constant)

emitted during Positron Emission

when an electron from the closest energy level falls into the nucleus, causing a proton to become a neutron

The excess energy of the nucleus is transferred to the orbital electron which is then ejected from the atom - a process in which the nucleus of an atom with excess energy releases that energy without altering its proton and neutron count

During Internal Conversion, the excess energy of the nucleus is transferred to this………which is then ejected from the atom

emitted as the atom attempts to become stable

- much more violent process - occurs when the nucleus is too large or too heavy. - occurs when a large atom (Z=82 above) loses 2 protons and 2 neutrons leaving a decay product. - Least penetrating and is absorbed by a paper.

- must be extremely unstable to emit alpha particles - Consists of two protons and two neutron bound together; its atomic mass number is 4.

occurs when the nucleus of an atom is still unstable even after a beta or alpha decay.

emits gamma radiation in order to become stable.

this is often left in an excited state which means it still has excess energy. when an alpha or beta decay occurs,

lost by emission of gamma rays instead of another beta or alpha decay,

a nuclear process in which a nuclei with excess energy following alpha or beta decay emits energy without changing the atomic number and atomic mass number.

- A series of transformations that a given radionuclide will undergo and what type of radiation it will emit - Most natural occurring radionuclides will undergo a series of transformation rather than a single step.

occurs in the decay chain when the rate of creation and decay of a radionuclide is the same rate.

cannot occur if the half-life of the decay product is much longer than that of the original radionuclide

occurs when the half-life of the original radionuclide and its product are similar

the half-life of the original radionuclide is longer than that of the product

the half-life of the decay product is longer than that of the original radionuclide

time required for a quantity of radioactivity to be reduced to one-half its original value.

The time required for the human body to eliminate one-half of the dose of any substances by biological process (sweating, urinating, defecation, or breathing). Applies for radio pharmaceuticals used during nuclear imaging and PET scans.

The combination of both physical and biologic half-life. Used when health physicists calculate the dose received from an internal radiation

- Father of Radioactivity - He placed uranium salts near a photographic plate covered with opaque paper and discovered to be fogged. - He showed that the rays emitted by uranium causes gases to ionize and that they differed from x-rays in that they could be deflected by an electric or magnetic field.

- extensively studied uranium - discovery of radium and polonium - Nobel Prize in Physics 1903

- a process wherein an unstable atom emits particles and energy to transform into another atom to become stable

how many dps in 1 curie

how many curie in 1 becquerel