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Chemistry
Radioactive Decay
Types:
1. Alpha (α) – an atom ejects a helium nucleus ( 2 protons and 2 neutrons ) from its own
nucleus
2. Beta (β)
a. Beta- – a neutron in the nucleus decays into a proton and an electron
b. Beta+ (positron) – a proton in the nucleus decays into a neutron and a positron
3. Gamma (γ) – an excited nucleus releases electromagnetic radiation in the form of a
gamma ray (most penetrating)
Formulas
1. Alpha –
2. Beta
a. Beta- –
b. Beta+ (positron) –
3. Gamma –
Examples
Polonium-210 undergoes alpha decay
Cesium-137 undergoes beta- decay
Potassium-40 undergoes beta+ decay
Nickel-68 undergoes gamma decay
or sometimes
2
Chemistry
Practice
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Tritium (Hydrogen-3) undergoes beta- decay
Uranium-238 undergoes alpha decay
Americium-241 undergoes alpha decay
Carbon-10 undergoes beta+ decay
Plutonium-238 undergoes alpha decay
Carbon-14 undergoes beta- decay
Lithium-7 undergoes gamma decay