类别 全部 - radiation - nucleus - energy

作者:Katia Alvarez 5 年以前

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Atomic Nucleus Homework

Radioactive decay involves several processes through which unstable atomic nuclei release energy to achieve a more stable state. Alpha decay occurs in very heavy nuclei and results in the emission of monoenergetic alpha particles, reducing both the atomic and mass numbers.

Atomic Nucleus Homework

Atomic Nucleus

Types of Radioactive decay

Electron Capture
Ex. Ga-67
Occurs when a orbital electron travels close to the Proton rich nucleus It is captured, and combined with a P+ to form a N

X-rays are emitted

Originates: electron shell
Positron Decay
Neutrino is created
Z # decreases by 1 A # remains the same
A Proton rich nucleus converts a P+ -> N A e+ (positron) is created

when the e+ is created it looses energy b/c its colliding with surrounding matter, it gets attracted to an electron and they spiral towards one another before annihilation. (mass of the e+ and e- is converted into pure EM energy)

Gamma Decay
Ex. Mo99-Tc-99m
Occurs if there is more than 100 keV of excess energy,
Isomeric Transition

change in the extranuclear portion of an atom from a high energy level to a lower level accompanied by the release of EM radiation = gamma radiation

Beta decay
Ex. I-131 -> Xe-131
Antineutrino is created (no electrical charge/mass)

needed to conserve energy in the decay it carries away the difference between B- particle energy and the decay energy.

Z # increases by 1 A # remains the same

B/c the Z # changed, a new element is formed

A neutron rich nucleus converts a N -> P+ An electron is created
Originates: nucleus
Alpha Decay
Z # decreases by 2 A # decreases by 4
Results from the decay of very heavy nuclei
Originates: in the nucleus

alpha particles are monoenergetic range in matter is very short