Nuclear/decay Flashcards
atomic number
bottom, number of protons
atomic mass
top number, protons and neutrons
what does stable mean
not radioactive
isotope
different neutrons, different mass numbers same atomic
alpha decay
element loses protons and forms new element, loses same amount of protons/neutrons (emits alpha particle, 2 protons/neutrons), pb —- Fe + 4 a etc
beta decay
too many neutrons, emits electron and turns a neutron to proton and makes new element, atomic mass/number dont change
heavy and light elements
heavy=alpha, light=beta
gamma decay
after beta decay, as nucleus still excited and energy releases gamma rays (y rays), travel at light speed, x rays emitted when electrons change orbit, electromagnetic radiation emitted
alpha particles
bulkier than beta, slowed easily by things like paper, 4 atomic mass, +2 charge, 2 protons and 2 neutrons
beta particles
need thick plastic/aluminium NOT THIN LEAD, not bulky, -1 charge, an ELECTRON, dont travel far, when electron stops it releases an xray
gamma ray
stopped by thick lead, no mass/charge, travels far
activity
amount of radioactivity (becquerels)
half life
time it takes for radioactive nuclei to half
rate of decay
measured by decay constant and half life, both inversely proportional (higher decay constant means lower half life)
equation and what does C and C(o) mean
C=C(o)EXP(-At), C is concentration at end of decay, C(o) is concentration before
einsten principle of mass/energy
E=mc(2), m is mass, c is speed of light, means sum of nucleus is less than the contents combined, about how mass turns to energy
mass defect
when mass of nucleus weighs less than the contents
Fusion
putting light elements together to make heavy elements but heavier elements are lighter than light elements as some goes to energy, sun uses fusion, good waste
fission
splitting heavy elements to light ones which releases energy, all nuclear reactors use this, bad waste
binding energy
amount of energy needed to split constituents in the nucleus, depends on mass number
