The periodic table is far more than a chart hanging on the wall of a chemistry classroom - it is the cornerstone of chemistry itself. Within its elegant structure lie all the known elements that make up the matter around us, from the air we breathe and the devices we use to the stars, planets, and galaxies that fill the universe. In many ways, it can be viewed as a kind of genome of matter: a framework that organizes the fundamental building blocks from which all substances are constructed. It is also a record of matter across time: the elements’ origins in the Big Bang, stars, and supernovae; humanity’s efforts to discover and understand them; and future frontiers beyond the modern table. In the sections that follow, we explore these ideas while considering emerging concepts that may reshape chemistry for generations to come.

The Origin of the Elements

Every element in the table has a cosmic origin, forged through a sequence of remarkable events that began nearly 14 billion years ago with the Big Bang.¹ In the earliest moments, the universe was an unimaginably hot sea of energy and quarks. As the universe expanded and cooled, quarks combined to form protons and neutrons, while electrons emerged as stable companions. During the first few minutes, protons formed the nuclei of hydrogen, the lightest element. Much of that primordial hydrogen has remained intact for nearly 14 billion years, passing through stars, clouds, planets, water, and living things. So, if you are 20 years old, many of the hydrogen atoms in your body are almost as old as the universe itself.

Stars became the next great element factories. Deep within their cores, hydrogen nuclei fused to form helium, releasing the energy that makes stars shine. Strikingly, the newly formed helium atoms, together with the abundant hydrogen present in the early universe, produced helium hydride ion (HeH⁺), widely regarded as the first molecular compound formed after the Big Bang. In a profound irony, the first chemical compound ever formed was a compound of helium - the archetypal inert noble gas, long considered incapable of chemical bonding.

As stars evolved, they fused helium into heavier elements and continued building successively larger nuclei through stellar nucleosynthesis, producing elements such as carbon, oxygen, silicon, and many others. This process can generate elements only up to iron, whose nucleus represents a turning point in the energetics of fusion.

The creation of elements heavier than iron requires even more dramatic events.¹ When massive stars exhaust their nuclear fuel, they can explode as supernovae, creating environments rich in neutrons. Under these extreme conditions, existing heavy nuclei, such as iron, rapidly capture neutrons:

The resulting nuclei are unstable and undergo beta decay:

Each beta decay increases the atomic number by one, converting an element into its neighbor on the periodic table. Through repeated cycles of neutron capture and beta decay, nature synthesizes many of the heaviest elements, including gold, lead, and uranium—the last naturally occurring element in the periodic table.

Humanity has further extended this cosmic story through nuclear technology.² Using nuclear reactors and particle accelerators, scientists have transformed naturally occurring elements into new ones. For example, plutonium can be produced from uranium, and decades of research have enabled the synthesis of elements beyond uranium, known as transuranium elements. The most recent additions to the periodic table—nihonium, moscovium, tennessine, and oganesson—represent the current frontier of elemental discovery.

A Deeper Appreciation of Synthetic Elements

Before moving on, it is worth taking a moment to appreciate the synthetic elements, which exemplify humanity’s ability to push beyond the boundaries of the known chemical world, reflecting not only our understanding of the fundamental nature of matter but also our capacity to create entirely new forms of it.

Among these elements, plutonium is particularly fascinating³ (Figure 1). It can be produced in quantities large enough to form a visible metal, allowing us to hold in our hands an element that was made by human ingenuity rather than by nature. Beyond its scientific significance, plutonium has important applications, from nuclear energy production to powering thermoelectric generators that have enabled spacecraft such as Voyager to explore the outer reaches of our solar system. Equally important, its chemistry is every bit as rich and intriguing as that of the more familiar elements. Plutonium exhibits multiple oxidation states, colorful solution chemistry, and complex bonding behavior, making it as worthy of chemical study as any transition metal.

Figure 1 - Plutonium: a synthetic element with rich chemistry and useful properties, a marvel of human creativity and scientific achievement. The right image shows aqueous solutions of plutonium in different oxidation states, with the test tubes containing Pu(III), Pu(IV), Pu(V), Pu(VI), and Pu(VII) species, respectively (as labeled). The Pu(III), Pu(IV), and Pu(VI) solutions are prepared in 1 M HClO₄, while Pu(V) is shown in NaClO₄ at pH 7; in all four cases, ClO₄⁻ serves as the counterion. In contrast, the Pu(VII) solution is shown in 2.5 M NaOH, where Na⁺ is the counter-cation. (Right image by U.S. Department of Energy, licensed under CC BY 3.0.; Left image by Los Alamos National Laboratory, via Wikimedia Commons, public domain)

The practical impact of synthetic elements extends well beyond plutonium. Many have found specialized applications that touch our daily lives in surprising ways. Technetium, the first element ever produced artificially, has become indispensable in modern medicine, used in millions of diagnostic imaging procedures each year. Americium helps protect homes as the active component in many smoke detectors, while californium serves as a powerful neutron source for industrial inspection, mineral exploration, scientific research, and security technologies used to detect hazardous materials.

These examples show us that synthetic elements are not merely exotic additions to the periodic table; they are useful materials whose unique properties enable technologies that would otherwise be impossible. From diagnosing disease and safeguarding homes to exploring space and advancing scientific discovery, synthetic elements demonstrate how fundamental research into the structure of matter can lead to transformative real-world applications.

The Emergence of the Periodic Table

Although the chemical elements themselves were formed billions of years ago, humans began identifying them only much later. In antiquity, only a handful of elements were known, including gold, iron, copper, carbon, and sulfur, valued for their practical uses and distinctive properties. During the era of alchemy, new elements such as arsenic and phosphorus were isolated, expanding humanity’s understanding of the material world. The birth of modern chemistry in the eighteenth and nineteenth centuries accelerated the discovery of elements such as oxygen, hydrogen, and potassium.

By 1869, scientists had identified 63 elements, providing enough information for Dmitri Mendeleev to arrange them into the first widely recognized periodic table, ordered primarily by atomic weight. Mendeleev’s classification gained widespread attention when several elements he had predicted - including gallium, scandium, and germanium- were discovered in the following years. As additional elements, including the noble gases, were discovered, the periodic table continued to grow. In 1913–1914, Henry Moseley demonstrated that the elements should be arranged according to atomic number rather than atomic weight, establishing the foundation of the periodic table as we know it today. Moseley’s work also revealed gaps corresponding to missing atomic numbers, including element 43, later identified as technetium. In 1937, Emilio Segrè and Carlo Perrier produced technetium, making it the first synthetic element.

The era of synthetic elements expanded further with the discovery of plutonium in 1940 by a team led by Glenn T. Seaborg. Since then, scientists have created increasingly heavier elements, extending the periodic table beyond the naturally occurring elements all the way to oganesson, the heaviest element currently known. Today, the modern periodic table is organized into 18 groups and 7 periods and includes a total of 118 recognized elements (Figure 2).

Figure 2 - The modern periodic table. (Image via Wikimedia Commons, licensed under CC BY-SA 4.0.)

The Anatomy of the Periodic Table

The periodic table may be viewed as a structured map of elemental families and recurring chemical behavior (Figure 2), with the alkali and alkaline earth metals constituting the s-block, the transition metals forming the d-block, the boron group through the noble gases comprising the p-block, and the lanthanides and actinides belonging to the f-block.

On the left reside the alkali metals, followed by the alkaline earth metals, while the central block is occupied by the transition metals, including the so-called coinage metals - copper, silver, and gold - sometimes informally referred to, in a nontechnical context, as the “Olympic medal group”. The right-hand block unfolds into the boron group, the carbon group - sometimes informally imagined as the “information group” due to carbon’s role in graphite pencils, silicon-based computing, and printing media - the pnictogens (nitrogen group), chalcogens (oxygen group), halogens, and noble gases, whose closed-shell electronic configurations confer chemical stability. Beneath the main body lie the lanthanides and actinides, often displayed separately for clarity but essential to the continuity of the periodic system.

Beyond uranium, all elements are transuranium and are synthesized artificially, while all elements with atomic number greater than bismuth are radioactive. Beginning around rutherfordium, elements are often described as superheavy because they are produced only in extremely small quantities and are typically short-lived. In broader chemical terminology, scandium, yttrium, and the lanthanides are collectively referred to as the rare earth elements. Gold, silver, and platinum are traditionally classified as precious metals due to their chemical stability and economic value, while the term heavy metals is a non-rigorous but widely used descriptor for dense elements, many of which—such as mercury, cadmium, and arsenic—are notably toxic in specific chemical forms.

Now, why is the periodic table called “periodic”? As atomic number increases, patterns in electron configuration repeat at regular intervals. The s-block elements have outer configurations of s¹ to s², the p-block elements range from s²p¹ to s²p⁶, the d-block involves filling the d orbitals from d¹ to d¹⁰, and the f-block involves filling the f orbitals from f¹ to f¹⁴. Because an element’s chemical behavior is mainly determined by its valence-electron configuration, elements with similar outer electron arrangements—especially those in the same vertical group—show similar reactivity.

The Elemental Reach of the Periodic Table

Modern chemistry reveals a striking continuity between the most fundamental building blocks of matter and the complexity of the world we engineer. At one extreme, a record-setting compound⁴ has been reported to incorporate 11 different elements within a single molecular framework, highlighting the extraordinary synthetic reach of coordination chemistry (Figure 3). An analogous example from nature is found in the D1 protein environment of Photosystem II, where a protein–cofactor assembly incorporates 11 different elements (C, H, O, N, Mg, P, S, Cl, Ca, Mn, and Fe), highlighting the complex molecular architectures found in biological systems.

Figure 3 - Compound containing 11 different elements (C, H, Au, B, Cl, F, N, O, P, Pt, and W) within a single molecule (Me = methyl group; Ph = phenyl group).

At a much larger scale, the design of a modern electric vehicle draws upon approximately 53 elements of the periodic table, spanning lightweight structural metals, rare earth magnets, conductive components, and advanced batteries.⁵Even the human body reflects this elemental diversity, containing roughly 59 elements,⁶ with the average empirical formula shown in Figure 4. This representation provides a clear counterpoint to public chemiophobia by emphasizing that “chemical” is not always synonymous with “harmful”.

Figure 4 – A conceptual empirical formula representing the elemental composition of the human body.

In parallel, the smartphone - arguably one of the most ubiquitous technological artifacts - embodies an even broader chemical footprint, incorporating materials derived from nearly 90% of the stable elements in the periodic table across its processing chips, display systems, sensors, and energy storage units.⁷ This phenomenal elemental diversity also invites reflection on patterns of consumption, particularly among younger users, who may benefit from appreciating the chemistry packed into these devices before replacing them in pursuit of incremental upgrades.

Seeing the Atoms of the Elements

For much of scientific history, atoms were regarded as theoretical entities whose existence could only be inferred from experimental evidence. This changed dramatically in the late twentieth century with the development of scanning probe microscopy. In 1989, researchers at IBM used a scanning tunneling microscope to position 35 xenon atoms on a nickel surface, arranging them to spell the company’s logo⁸ (Figure 5). This landmark achievement demonstrated not only the ability to image individual atoms but also to manipulate them with great precision. Modern microscopy techniques have since provided increasingly detailed views of atoms and molecules. These advances make clear that, although atoms are often described as being mostly empty space, they possess both electronic and nuclear density, which makes them structurally robust.

Figure 5 - In 1989, researchers at IBM arranged 35 xenon atoms on a nickel surface using a scanning tunneling microscope, demonstrating the ability to image and manipulate individual atoms. Although xenon is normally a gas, the experiment was carried out at about 4 K (−269 °C) by cooling the microscope chamber and the nickel crystal with liquid helium. At this temperature, xenon atoms have very little thermal energy and adsorb (stick) to the nickel surface, allowing them to be positioned one by one. (Courtesy of IBM Research Division)

Looking ahead, the ability to image and manipulate individual atoms raises the possibility of performing highly selective chemical reactions with a microscope. Coupled with advances in quantum computing and artificial intelligence, such as AI systems used for protein-structure prediction and molecular design, scanning-probe techniques could eventually support the design and construction of molecules atom by atom. In principle, an AI-guided system could identify a promising drug candidate for a particular disease, while a microscope-based platform could position atoms or molecular building blocks with extraordinary precision. Although achieving reactions at useful industrial scales - approaching Avogadro-scale quantities - would require major advances in speed, automation, and reproducibility, such technology could transform chemical synthesis. Rather than relying solely on conventional glassware-based laboratories, future chemistry may incorporate integrated platforms in which AI, quantum computation, and nanoscale microscopy work together to design, assemble, and test new materials and medicines.

Such a system would represent a genuine revolution in chemistry, transforming the laboratory from a primarily macroscopic workspace into an AI-guided, atomically precise manufacturing environment.

How Far Can the Periodic Table Extend?

The discovery of increasingly heavier elements naturally raises an intriguing question: does the periodic table have an ultimate limit? Although there is no consensus, scientists have developed several theoretical models to estimate the maximum possible atomic number.^9-11

One widely cited model that incorporates relativistic effects is based on Dirac–Fock calculations.⁹ In such approaches, relativistic contributions become increasingly significant with rising atomic number, as electron velocities increase with Z and eventually approach relativistic regimes constrained by the speed of light. Within this framework, Pekka Pyykkö proposed that the periodic table may have an upper limit around atomic number Z ≈ 172. In this extended arrangement, element 172 would occupy the noble-gas group and has occasionally been given the informal placeholder name “ramson” (Rs), in honor of Sir William Ramsay, whose work was closely associated with the discovery of the noble gases. This designation, however, is not recognized by IUPAC. Under these extrapolations, the extended periodic table would contain 18 groups and up to 9 periods, comprising a total of 172 elements, as illustrated in Pyykkö’s proposed periodic table (Figure 6).

Figure 6 - A hypothetical extension of the periodic table to atomic number 172 (Pyykkö’s periodic table). (Image via Wikimedia Commons, licensed under CC BY-SA 3.0.)

At present, most synthetic elements are known to be highly unstable, with very short lifetimes ranging from microseconds to a few seconds, although a few exceptions persist for several minutes. They are also produced in extremely small quantities - usually on the order of only a few atoms. Why, then, do scientists continue to pursue the discovery of new elements?

The motivation for such efforts stems from the belief that we may encounter an island of stability,¹² giving rise to elements with properties we cannot even imagine—perhaps, humorously, like “transformium”, the fictional shape-shifting metal from the Transformers films.

In this context, recent evidence has suggested the possible existence of new elements with very high atomic numbers.¹³Astronomical observations indicate that some asteroids in our solar system may have mass densities exceeding that of osmium (Z = 76), the densest known chemical element on Earth, with a density of 22.5 g/cm³. In particular, asteroid 33 Polyhymnia, located in the main asteroid belt between Mars and Jupiter, has been reported to have an exceptionally high estimated density of 75.3 g/cm³—almost three times that of osmium.

Scientists suggest that the extremely high density of this asteroid may be explained by the presence within its structure of unknown elements beyond the modern periodic table, such as those near Z = 164 - which are predicted to exhibit mass density values between 36.0 and 68.4 g/cm³ - thus making them plausible candidates. However, these interpretations are still uncertain and have not been confirmed.

Driven by the goal of extending the periodic table, researchers across several leading superheavy element collaborations have already initiated experimental campaigns aimed at the synthesis of elements 119 and 120, envisioned as the next alkali and alkaline earth metals that would inaugurate the 8th period. While no confirmed atoms have yet been attributed to either element, the continued refinement of accelerator technology and target preparation keeps open the possibility that these elusive members of period 8 may eventually be brought within experimental reach, extending the periodic table into a new frontier of chemical exploration.

Summary

The periodic table is undoubtedly one of science’s greatest achievements, providing a remarkably elegant framework for organizing all known chemical elements and revealing the underlying order of matter. But despite its apparent completeness, it continues to be a dynamic scientific frontier. As a result, researchers are currently pursuing the synthesis of elements 119 and 120, expected to become the first alkali metal and alkaline earth metal of the eighth period. Their eventual discovery would not simply add two new boxes to the table; it would extend our understanding of atomic structure and open the door to unexplored regions of chemistry.

It also reminds us of the immense creative potential of chemistry. With only eight musical notes, humanity has composed an astonishing diversity of melodies and musical styles, and new ones continue to emerge. Imagine, then, what can be achieved with 118 chemical elements. Although scientists have already identified tens of millions of compounds, estimates suggest that the total number of potentially accessible compounds - the so-called chemical space - may reach 10⁶⁰ or even beyond. In that sense, the fraction of chemistry we have explored so far is effectively 0%. Somewhere within this vast chemical landscape may lie new elements, previously unknown compounds, revolutionary materials, cleaner energy technologies, and life-saving medicines that remain unimagined.

And to every young reader of this story: look in the mirror - you may be seeing the portrait of the discoverer of the next element. Just make sure your last name begins with J or Q: they are the only letters not yet represented in an element name, so perhaps the next element could one day be named after you, junior (Jr) quester (Qs).

1.      Penovich, K. Formation of the Elements. Lawrence Berkeley National Laboratory. https://aether.lbl.gov/www/tour/elements/element.html (accessed 2026-07-3).

2.      Renneboog, R. M. Man-Made Elements. EBSCO Research Starters, 2022. https://www.ebsco.com/research-starters/chemistry/man-made-elements (accessed 2026-07-3).

3.      Plutonium. Wikipedia, The Free Encyclopedia. https://en.wikipedia.org/wiki/Plutonium (accessed 2026-07-3).

4.      Faust, R.; Knaus, G.; Siemeling, U.; Quadbeck-Seeger, H.-J., Ed. World Records in Chemistry. Wiley-VCH: Weinheim, 1999.

5.      Peplow, M. How Many Chemical Elements Does It Take to Build a Car? inChemistry, 2021.https://inchemistry.acs.org/atomic-news/elements-to-build-a-car.html (accessed 2026-07-3).

6.      Human Molecular Formula. EOHT.info. https://www.eoht.info/page/human-molecular-formula (accessed 2026-07-3).

7.      Brunning, A. The Chemical Elements of a Smartphone. Compound Interest, 2014. https://www.compoundchem.com/2014/02/19/the-chemical-elements-of-a-smartphone/ (accessed 2026-07-3).

8.      IBM (atoms). Wikipedia, The Free Encyclopedia. https://en.wikipedia.org/wiki/IBM_(atoms) (accessed 2026-07-3).

9.      Pyykkö, P. A Suggested Periodic Table up to Z ≤ 172, Based on Dirac–Fock Calculations on Atoms and Ions. Phys. Chem. Chem. Phys. 2011, 13, 161–168.

10.    Seaborg, G. T.; Loveland, W. D. The Search for New Elements. In The New Chemistry; Hall, N., Ed.; Cambridge University Press, 2000; pp. 1–31.

11.    Kuntzleman, T. Search for the Final Element. ChemEd X, 2016. https://www.chemedx.org/blog/search-final-element (accessed 2026-07-3).

12.    U.S. Department of Energy, Office of Science. DOE Explains: Superheavy Elements.https://www.energy.gov/science/doe-explainssuperheavy-elements (accessed 2026-07-3).

13.       Felton, J. Asteroid 33 Polyhymnia May Contain Elements Outside the Periodic Table. IFLScience, 2024. https://www.iflscience.com/asteroid-33-polyhymnia-may-contain-elements-outside-the-periodic-table-72775