radioactive decay Flashcards
is the nucleus of a chemical element fixed
not always
what can an unstable nucleus do
It can change spontaneously from one element to another (this is radioactivity)
what can atoms do with their electrons
Atoms can swap and change electrons when they bond
what does a radioactive nuclei do
This radioactive nuclei shoots out an electron, loses a neutron, gains a proton and then transforms into another element
what speed does the fast moving electron go
very fast
how many types of particles do radioactive nuclei give off
Radioactive nuclei can give off two particles, but never together
what are the particles called
alpha and beta
what is the name of the ejected electron
beta particle
what is an alpha particle
An alpha particle (helium) is made up of two protons and two neutrons. It is 8000x bigger than a beta particle
how far can alpha and beta particles go
Alpha particles cannot go very far in the air, yet beta particles can penetrate much further into objects
what is the third part of radioactive decay
Gamma is not a particle at all, but is still sometimes ejected by the nuclei.
what are gamma waves
They are made up of electromagnetic waves and are found in microwaves and light
what can gamma waves do
Gamma waves are able to move through your body, and move much faster than visible light. Gamma is used to zap the bacteria in fruit to increase its shelf life or in radiotherapy to kill cancer cells
what can radioactive substances do?
Radioactive substances get hot, and generate power
what is ionisation
Ionization: the more abruptly nuclear radiation is slowed down, the more damage it does when the atoms hit. Alpha causes the most ionization as it crushes into other atoms and gamma the least
what is the most dangerous particle
Although alpha particles cannot penetrate the skin, if ingested or inhaled, they can kill you
ALPHA
a helium nucleus, stopped by air
BETA
an electron, stopped by aluminium
GAMMA
not a particle, just energy, stopped by thick lead
what happens during alpha radiation
parent nucleus - alpha particle (through radiation) = new nucleus (daughter isotope)
what happens during beta decay
parent - beta particle (an electron) = new nucleus
what happens during gamma decay
parent (excited nuclear state) - gamma ray = daughter
mass during radioactive decay
alpha - decreased by 4, atomic number decreased by 2
beta - mass remains the same, atomic number increases by one
gamma - mass remains the same, atomic number stays the same
penetrating power
alpha - stopped by a piece of paper
beta - stopped/slowed by aluminium
gamma - shielded by thick lead or concrete
