Chem Test Flashcards
What are the two categories of isotopes?
Stable and unstable
What are radioactive isotopes?
Isotopes of certain unstable elements that spontaneously omit particles and energy from the nucleus
Who is the first person to accidentally observe radioactivity?
Henri bacquerel
What is radioactivity?
The process by which nuclei spontaneously undergo transformation to other isotopes with corresponding release of radiation
What are the three types of radiation?
Alpha, beta and gamma
What is alpha decay?
The emission of alpha particles, two protons and two neutrons. it can travel a few inches and be stopped by paper or clothing. +2e charge
What is beta decay?
Electrons excluded from the nucleus when neutrons decay. beta particles have the same charge and mass as normal electrons they can be stopped by aluminum or a simple block of wood
What is gamma decay?
Gamma radiation is electronic energy that is released. Rays are electronic waves. They have no mass gamma radiation has no charge. It’s the most penetrating and can be stopped by a 1 m thick concrete or several centimeters thick sheet of lead.
What is positron decay ?
The reverse of better decay
What is an electron capture?
When the closest energy levels fall into the nucleus, which causes the proton to be a neutron
How many nuclei are known?
There are more than 1500 different nuclei known only 264 of those are stable and do not decay
What is nuclear medicine?
Uses radiation to provide diagnostic information about the functioning of a persons organs or treat them diagnostic procedures using radioisotopes are now routine
What is a half-life?
The time required for one half-life of a nuclei of a radioisotope sample to decay
What is nuclear fission
When a nucleus of a certain isotope or bombarded with neutrons, they undergo vision, the splitting of a nucleus into smaller fragments
What is nuclear fusion
It occurs when nuclei combined to produce a nucleus of greater mass in solar fusion hydrogen, nuclei fuse to make helium
