a change that affects the nucleus of an atom
nuclear reaction

alpha decay
A stable atom undergoes radioactive decay to become unstable.
An unstable atom undergoes radioactive decay to become stable.
a nuclear reaction in which an unstable nucleus gives off energy and, sometimes, particles
radioactive decay

gamma decay
Uranium is used as fuel in nuclear fusion reactors.
Uranium is used as fuel in nuclear fission reactors.
a nuclear reaction in which a large, unstable nucleus breaks into two smaller nuclei
nuclear fission

beta decay
Isotopes of the same element are different from each other because they have different numbers of protons.
Isotopes of the same element are different from each other because they have different numbers of neutrons.
the process of whihc nuclei of small atoms combine to form a new, more massive nucleus
nuclear fusion
A uranium-235 (U) nucleus undergoes alpha decay. What new isotope is created?
Thorium-231 is created.
Nuclear chain reactions in power plants are controlled by using a small amount of fuel.
Nuclear chain reactions in power plants are controlled by control rods which absorb neutrons.
atoms with the same number of protons but different numbers of neutrons
isotopes
Carbon-14 undergoes beta-minus deacy in which one of its neutrons changes into a proton and it gives off an electron. What new isotope is created?
Nitrogen-14 is created.
A challenge we face in performing fusion reactions on Earth is finding fuel.
Fusion reactions can be done using hydrogen which can easily be found in water.