The key difference between radioactivity and transmutation is that radioactivity refers to natural transmutation, whereas transmutation refers to the change of one chemical element into another via either natural or artificial means.
Both radioactivity and transmutation are chemical processes that involve the change of atomic nuclei to form a new chemical element from an existing chemical element. Radioactivity is a type of transmutation process.
CONTENTS
1. Overview and Key Difference
2. What is Radioactivity
3. What is Transmutation
4. Side by Side Comparison – Radioactivity vs Transmutation in Tabular Form
5. Summary
What is Radioactivity?
Radioactivity is an inorganic process of spontaneous nuclear transformation that results in the formation of new elements. This means radioactivity is the ability of a substance to release radiation. We can find many different radioactive elements in nature, and some are synthetic as well. Typically, the nucleus of a normal (non-radioactive) atom is stable. In the nuclei of radioactive elements, there is an imbalance of neutrons to protons ratio, which makes them unstable. Therefore, these nuclei tend to emit particles in order to become stable, and this process is named as the radioactive decay.
Usually, a radioactive element has a rate of decaying: half-life. The half-life of a radioactive element describes the time that a radioactive element requires to decrease to one half of its original quantity. The resulting transformations include Alpha particle emission, Beta particle emission and orbital electron capture. Alpha particles emitted from a nucleus of an atom when the neutron to proton ratio is too low. For example, Th-228 is a radioactive element which can emit alpha particles with different energies. In Beta particle emission, a neutron inside a nucleus is converted to a proton by emitting a beta particle. P-32, H-3, C-14 are pure beta emitters. Radioactivity is measured by the units, Becquerel or Curie.
When radioactivity takes place in nature, we call it natural radioactivity. Uranium is the heaviest naturally occurring element (atomic number 92). However, these unstable nuclei can be made in labs via bombarding them with slow-moving neutrons. Then we can call it artificial radioactivity. Though there are radioactive isotopes of thorium and Uranium, artificial radioactivity means that we are creating a series of trans-uranium elements that are capable of radioactivity.
What is Transmutation?
Transmutation is the chemical process of changing the structure of atoms in the atomic nuclei, which leads to the conversion of a chemical element into a different chemical element. There are two types of transmutation as natural and artificial transmutation.
Natural transmutation is nuclear transmutation that occurs naturally. In this process, the number of protons or neutrons in the atomic nuclei changes, causing the chemical element to change. This type of natural transmutation occurs in the core of stars; we call it stellar nucleosynthesis (in the core of the stars, nuclear fusion reactions create new chemical elements). In most stars, these fusion reactions occur involving hydrogen and helium. However, large stars can undergo chemical fusion reactions via heavy elements such as iron.
Figure 01: Stellar Nucleosynthesis
Artificial transmutation is a type of transmutation we can perform as an artificial process. This type of transmutations occurs via the bombardment of an atomic nucleus with another particle. This reaction can convert a particular chemical element into a different chemical element. The first experimental reaction for this reaction was the bombardment of a nitrogen atom with an alpha particle to produce oxygen. Usually, the newly formed chemical element shows radioactivity. We name these elements as tracer elements. The most common particles that are used for bombardment are alpha particles and deuteron.
What is the Difference Between Radioactivity and Transmutation?
Both radioactivity and transmutation are chemical processes that involve the change of atomic nuclei to form a new chemical element from an existing chemical element. The key difference between radioactivity and transmutation is that radioactivity refers to the natural transmutation, whereas transmutation refers to the change of one chemical element into another via either natural or artificial means.
Below infographic summarizes the difference between radioactivity and transmutation.
Summary – Radioactivity vs Transmutation
Both radioactivity and transmutation are chemical processes that involve the change of atomic nuclei to form a new chemical element from an existing chemical element. The key difference between radioactivity and transmutation is that radioactivity refers to the natural transmutation, whereas transmutation refers to the change of one chemical element into another via either natural or artificial means.
Reference:
1. “4.12: Transmutation and Radioactivity.” Chemistry LibreTexts, Libretexts, 7 Feb. 2020, Available here.
2. “Transmutation.” Encyclopædia Britannica, Encyclopædia Britannica, Inc., 14 Apr. 2009, Available here.
Image Courtesy:
1. “Keplers supernova” By NASA/ESA/JHU/R.Sankrit & W.Blair – Larger version uploaded from a NASA-sponsored site. Per Bridgeman Art Library v. Corel Corp.(Public Domain) via Commons Wikimedia