Isotopes and Nuclear Radiation + Nuclear Equations Flashcards
what is a isotope
atoms with the same number of protons, but different number of neurons
which subatomic particle determines the element
protons
what does the atomic number represent
number of protons
what does the mass number show
number of protons + neutrons
what is the process of radioactive decay
when unstable nuclei decay into other elements and give out radiation as they try to become more stable
what are Alpha particles
Helium Nuclei - 2 neutrons + 2 protons
what can alpha particles be stopped by
- 5 cm of air
- thin sheet of paper
what is ionising radiation
radiation that knocks electrons off atoms, creating positive ions
how is alpha radiation used in smoke detectors
- it ionises air particles cuasing a current to flow
- if smoke in air - it binds to ions - breaks circuit current flow
- alarm sounds
is alpha strongly or weakly ionising and what is the effect
Strongly ionising = travels the least distance
why are alpha particles strongly ionising
- large size
- strong charge 2+
what is a beta particle
a fast moving electron released by the nucleus
what is the mass and charge of a beta particle
- virtually no mass
- charge = -1
what level of ionising is beta and what is the effect
moderately ionising –> penetrate moderately far into materials before colliding
what can stop beta radiation
- aluminium sheet - 5mm
- 1m of air