Chemistry Unit 3 - Nuclear Chemistry

color code: red

radioactive

substances that release ionizing radiation to the environment

ionization

the process of stripping away an electron from a molecule

transmutation

the conversion of one element to another, involving a change in the atom’s nucleus

radioactive decay

the process by which an unstable nucleus decays into a more stable nucleus, releasing energy in the process

half-life

the time it takes for half of a sample of a radioactive isotope to decay

spontaneous decay

a form of radioactive decay in which a nucleus splits into two lighter nuclei

emanation

emission; something that is produced

radioactive decay has four possible emanations (alpha, beta, positron, gamma)

alpha particle

a product of radioactive decay; the weakest form of ionizing radiation, which can be stopped by paper, consisting of a helium nucleus

beta particle

a product of radioactive decay; a form of ionizing radiation that can be stopped by aluminum, consisting of an electron or a positron

positron

a product of radioactive decay; an electron with a positive charge; an example of antimatter

gamma radiation

a product of radioactive decay; the strongest form of ionizing radiation, which can be stopped by lead, consisting of an electromagnetic ray

fission

the splitting of a heavy nucleus into smaller, lighter nuclei

critical mass

the mass that must be maintained to sustain a chain nuclear fission reaction; recognizable because of their having two reactants

fusion

the combining of two light nuclei into one heavier nucleus

binding energy

the energy released when nucleons form a nucleus

artificial transmutation

also called artificial radioactivity; the process by which new isotopes or elements are made by bombarding a target nucleus with another particle of appropriate energy and mass

C-14

an isotope of carbon that releases beta radiation and is used as a tracer molecule and for radioactive dating, with a half-life of 5715 years

I-131

an isotope of iodine that releases beta radiation and is used to diagnose thyroid disorders, with a half-life of 8.021 days

Co-60

an isotope of cobalt that releases gamma rays and is used in radiation therapy to kill cancer cells, with a half-life of 5.271 years

82

the atomic number of the last element (lead; Pb) with stable isotopes; all isotopes of the elements after element 82 are radioactive

U-238 to Pb-206

the decay series of the radioactive isotope uranium-238, ending at the stable isotope lead-206

breeder reactors

a nuclear reactor that generates more fissile material than it consumes, due to the processing of spent fuel into more useable fuel

fuel in fuel rods

usually U-235 or Pu-239

control rods

contains boronated water in case control rods break - boron and cadmium absorb neutrons

moderator

slows the extra neutrons in a nuclear reactor, typically water or liquid sodium

coolant

water or deuterium oxide (heavy water)

shielding

lead, concrete (reinforced), water

chain reaction

the process by which the product of one reaction leads to another in a domino effect; a self-sustaining reaction