Nuclear Decay Graphic www labinitio com Nuclear Symbols
Nuclear Decay Graphic: www. lab-initio. com
Nuclear Symbols Mass number, A (p+ + no) Atomic number, Z (number of p+) Element symbol
Balancing Nuclear Equations Areactants 235 92 + 1 + 0 = Aproducts = 142 + 91 + 3(1) = + 36 + 3(0) 56 Zreactants = Zproducts
Balancing Nuclear Equations #2 226 = 4 + ____ 222 86 Rn 88 = 2 + ___ 86 Atomic number 86 is radon, Rn
Balancing Nuclear Equations #3 95 235 + 1 = 139 + 2(1) + ____ 95 39 39 92 + 0 = 53 + 2(0) + ____ Atomic number 39 is yttrium, Y Y
Alpha Decay Alpha production (a): an alpha particle is a helium nucleus Alpha decay is limited to heavy, radioactive nuclei
Alpha Radiation Limited to VERY large nucleii.
Beta Decay Beta production (b): A beta particle is an electron ejected from the nucleus Beta emission converts a neutron to a proton
Beta Radiation Converts a neutron into a proton.
Gamma Ray Production Gamma ray production (g): Gamma rays are high energy photons produced in association with other forms of decay. Gamma rays are massless and do not, by themselves, change the nucleus
Gamma Ray Production Gamma ray production (g): Gamma rays are high energy photons produced in association with other forms of decay. Gamma rays are massless and do not, by themselves, change the nucleus
Positron Production Positron emission: Positrons are the antiparticle of the electron Positron emission converts a proton to a neutron
Electron Capture Electron capture: (inner-orbital electron is captured by the nucleus) Electron capture converts a proton to a neutron
Types of Radiation
Nuclear Stability Decay will occur in such a way as to return a nucleus to the band (line) of stability. The most stable nuclide is Iron-56 If Z > 83, the nuclide is radioactive Graphic – Wikimedia user : Napy 1 kenobi
A Decay Series A radioactive nucleus reaches a stable state by a series of steps Graphic – Wikimedia Commons User Tosaka
Half-life Graphic - http: //cafreetextbooks. ck 12. org/science/CK 12_Earth_Science_rev. pdf
Decay Kinetics Decay occurs by first order kinetics (the rate of decay is proportional to the number of nuclides present) N 0 = number of nuclides present initially N = number of nuclides remaining at time t k = rate constant t = elapsed time
Calculating Half-life t 1/2 = Half-life (units dependent on rate constant, k)
Sample Half-Lives
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