Unit 1, Nuclear chemistry

chapter 24, textbook

stable

a nucleus that remains intact indefinitely

instable

a nucleus that experiences spontaneous decay

radioactivity

the spontaneous disintegration of a nucleus by emission

nuclear change

forms new elements by means of reactions

nucleons

the elementary particles that make up the nucleus

nuclide

each composition of a nucleus

isotope

a variation of the amount of neutrons an element has

radioisotope

an unstable nucleus of a particular isotope

X

the symbol for the element used in nuclide notation

A

the stand-in for mass of a nuclide in nuclide notation (found on the upper right), aka the amount of nucleons in the nuclide

Z

stand-in for the atomic number of the nuclide in nuclide notation (found in lower right

mass number

the mass of nucleons found in the nuclide, often found listed after the element name

parent

the reactant (element) before it has decayed

daughter

the product nuclide after decay

alpha decay

a nuclear process by which an atom loses two protons and two neutrons

alpha particle

a, 4/2a, 4/2He

beta decay

a radioactive process where a nucleus expels a particle of negative charge, converting a neutron to a proton

Beta particle

a sort of high speed electron that is expelled when a neutron becomes a proton

positron emission

the process by which a proton becomes a neutron

positron

the antiparticle of an electron that has the same mass but opposite charge

Electron capture

the process of a nucleus drawing in an electron from a low energy level

gamma emission

high energy photons exiting the nucleus (aka y emission)

y emission

a process that accompanies most nuclear processes because it happens when the nucleus is excited

band of stability

a graph that uses the number of neutrons and protons to predict likelyhood of decay

strong force

the attractive force between all nucleons that operates only over short distances

even

over half of all stable nuclides have both N and Z values that are this, suggesting that there are important patterns of nuclear stability

nucleon energy levels

the theorized counter part of electron levels in which nuclei have an optimal amount of nucleons

rules of stability

N/Z>1, Z<83,

neutron rich

this kind of nuclide is unstable and will undergo beta decay to stabalize

proton rich

this kind of nuclide is unstable and will undergo positron emission to stabilize or electron capture (more common among heavier elements)

Heavy

these kinds of nuclides are unstable and will most likely go through alpha decay

atomic mass

the average weight of a stable element, if a nuclide deviates significantly from it, it will probably go through a nuclear reaction

decay series

a multistep process to form a stable daughter nuclide

ionization counters

detects radioactive emissions as they ionize a gas

scintillation counters

detect radiation by its ability to excite atoms into creating light

Activity (A)

decay rate

Decay rate

change in nuclei/change in time

Bequerel

SI unit for measuring radioactivity (1 disintegration per second)

Curie

a common unit for measuring radioactivity that is much larger than the becquerel