Because transmutation, the change of one element into another, is only accomplished by some kind of change in the nucleus of an atom. It's a nuclear change, and a nuclear reaction is the only change that will facilitate transmutation.
Nuclear transmutation is a rather general term for a change in the nucleus of an atom. This change can be any one of several different types. The nucleus can either lose a particle or two in radioactive decay, or it might absorb a particle and undergo change in that way. The key is that the change in the nucleus actually changes the atom involved from one element into another. There are a number of different processes that cause nuclear transmutation, and one is radioactive decay. Links can be found below, and if you follow them, you'll find more information.
One example would be, uranium-238 decays into thorium-
234 and an (alpha) particle.
The disintegration of U-235 to Th-231:
235U----------------alpha particle----------------------231Th
Nuclear decay or radioactive bombardment.
Nuclear fission splits an atom of one element into two atoms of two different elements. This is not usually called transmutation. However, fission is accompanied by subsequent steps, which usually include transmutation.
Transitions between various stages of electron excitement.
There are four types of nuclear reactions. Fusion Fission Radioactive Decay Artificial Transmutation
nuclear fission
Yes.
transmutation, neutrons
When an element undergoes nuclear transmutation the result is a completely different element or isotope. All transmutation occurs through decay or nuclear reaction.
In nuclear science, transmutation is where one chemical element or isotope is converted into another. It occurs when materials decay, or it can be caused by nuclear reaction.
Transmutation is a nuclear reaction.Transmutation by chemical reactions is only a phantasy of the Middle Ages.
Nuclear decay or radioactive bombardment.
Nuclear fission splits an atom of one element into two atoms of two different elements. This is not usually called transmutation. However, fission is accompanied by subsequent steps, which usually include transmutation.
Nuclear reactions may or may not involve nuclear transmutation. We need to split hairs here to arrive at the correct answer, and the answer involves the definition of the word transmutation. We sometimes think of transmutation as the changing of one element to another. Fission and fusion reactions do this, and many kinds of radioactive decay also convert one element into another. But there are some kinds of nuclear reactions that do not change an atom from one element to another, but instead change it from one isotope of a given element into another isotope of that element. There are a number of examples of this, and one is where isotopes of a given element absorb a neutron and become another isotope of that element. A given nucleus incorporates the neutron into its nuclear arrangement and the next heavier isotope of that element is created. If a "strict" definition of transmutation is used where it means a nuclear reaction that changes one element into another, then no, this does not always happen as illustrated above with the example of neutron absorption. If a more general interpretation of the term is used where we say that the nucleus transmutes meaning changes configuration, then yes, nuclear reactions involve nuclear transmutation.
Transmutation of elements refers to the conversion of one chemical element into another. This occurs in nuclear reactions or through radioactive decay.
Transitions between various stages of electron excitement.
There are four types of nuclear reactions. Fusion Fission Radioactive Decay Artificial Transmutation
"Transmutation" or possibly "nuclear fusion."