The equation above outlines the formation of a helium nucleus. The number of nucleons remains the same on both sides. When four protons fuse a helium nucleus is formed, energy given off and 2 positrons ejected. The ejection of two positrons turns two protons into neutrons.
The animation on the left shows this reaction.
|The animation on the right shows the nuclear fission reaction of lithium. The lithium nucleus absorbs a neutron and splits into a hydrogen and helium nucleus(alpha particle). Once again note that the number of nucleons is the same on both sides of the equation.
|Helium decays to form a lithium nucleus with the release of an electron. Notice the number of nucleons is the same on both sides of the equation. A neutron decays with the release of an electron to form a proton. The atomic number increases from 2 to 3 but the atomic mass number remains the same at 4 nucleons.
-a positron is emitted when
a proton decays to a neutron
Identify "X" in the following nuclear reactions.
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