The 10 Most Famous Chemists in History

Mario Molina was a Mexican-American chemist who won the Nobel Prize in Chemistry in 1995 for his pioneering work on the formation and breakdown of the ozone layer. He was the first to discover that chlorofluorocarbons (CFCs) could destroy the ozone layer. In 1974, Molina and Rowland identified that CFCs had the potential to deplete the ozone. These chemicals, used in refrigerants, aerosols, and foam production, laid the foundation for the modern refrigerators that no longer rely on these substances.

His research started as a theoretical model based on computer simulations, but his findings showed that CFCs could indeed break down ozone under the conditions found in the upper atmosphere. Molina's theory suggested that ultraviolet light could break apart oxygen molecules, creating oxygen atoms, which could then interact with CFCs, releasing chlorine atoms, among other byproducts. Over the next two decades, Molina and Rowland became key figures in warning the world about the dangers of CFCs and the depletion of the ozone layer. Despite initial resistance, their work led to the first U.S. ban on CFCs in aerosol sprays in 1978, followed by similar measures in Canada, Norway, and Sweden.

Mexico City became a case study for this research and is now home to the Centro Mario Molina, an institution dedicated to addressing climate change, sustainable development, and energy efficiency challenges. Scientists, environmentalists, policymakers, and CFC producers debated Molina's theories for years. In 2013, President Barack Obama awarded Molina the Presidential Medal of Freedom for his contributions as a “visionary chemist and environmental scientist.”

Michael Faraday was a British chemist and physicist who made groundbreaking contributions to electromagnetism and electrochemistry. Faraday became one of the greatest scientists of the 19th century, beginning his career as a chemist. He authored a practical chemistry guide, showcasing his mastery of technical aspects and discovering several new organic compounds, including benzene. He was also the first to liquefy a so-called 'permanent' gas, a substance once believed incapable of being liquefied.

Faraday's most significant achievements were in the fields of electricity and magnetism. He was the first to generate an electric current using a magnetic field, invented the electric motor and the first electric generator, demonstrated the connection between electricity and chemical bonding, and uncovered the effect of magnetism on light. Faraday also named and studied the special behavior of materials in strong magnetic fields. His experimental work and theories provided the foundation upon which James Clerk Maxwell developed the classical theory of electromagnetism. In 1820, Faraday synthesized the first known compounds of carbon and chlorine by replacing hydrogen with chlorine in “olefin gas” (ethylene), marking the first substitution reaction. In 1825, through his work with illuminating gases, Faraday isolated and described benzene. During the 1820s, he also conducted pioneering research on steel alloys, laying the groundwork for the fields of metallurgy and material science.

Alfred Nobel was born in Stockholm, Sweden, and was a chemist, inventor, and entrepreneur, best known for inventing dynamite and establishing the prestigious Nobel Prizes. His family was descended from Olof Rudbeck, Sweden's most famous technical genius of the 17th century, during a time when Sweden was a dominant power in Northern Europe. Nobel was fluent in multiple languages, wrote poetry and plays, and held progressive views on social and peace issues for his time.

In 1863, Alfred Nobel invented a practical explosive device that consisted of a wooden plug inserted into a large amount of nitroglycerin, contained in a metal box. The ignition of small, electrically charged black powder grains in the plug initiated a much stronger explosion of the liquid nitroglycerin. This invention marked the beginning of Nobel's fame as both an inventor and a manufacturer of explosives. In 1865, Nobel further improved his detonating mechanism by creating the 'detonator cap,' a small metal cap containing mercury fulminate that could be ignited by a shock or moderate heat. This invention helped pave the way for modern high explosives.

Nobel's second major invention came in 1867, when he patented dynamite (derived from the Greek word 'dynamis,' meaning 'power') in both the UK (1867) and the United States (1868). Dynamite brought Nobel worldwide recognition and became widely used in tunneling, canal building, railway construction, and roadworks. In 1875, Nobel invented a more powerful form of dynamite, known as gelignite, and patented it the following year. Beyond explosives, Nobel also developed inventions such as synthetic silk and leather.

Rosalind Franklin was a British chemist and biophysicist, known for her groundbreaking work in discovering the molecular structure of deoxyribonucleic acid (DNA), the component of chromosomes responsible for encoding genetic information. Franklin also made significant contributions to the study of viruses, helping to lay the foundations for the field of structural virology. From 1947 to 1950, she worked with Jacques Mesring at the State Chemical Laboratory in Paris, focusing on X-ray diffraction technology. This research led to her studies on structural changes caused by the formation of graphite in carbon atoms subjected to heat—work that proved valuable for the coke industry.

In 1951, Franklin joined the Biophysics Department at King's College London as a research associate. There, she applied X-ray diffraction techniques to study DNA, and soon identified the molecule's density and, crucially, that it existed in a helical form. Her work refining X-ray diffraction images of DNA molecules laid the groundwork for James Watson and Francis Crick's 1953 discovery that DNA has a double-helix structure, with two DNA strands coiling around each other. Franklin also collaborated on research showing that RNA in certain viruses is embedded within its protein shell, not in its central cavity, and that this RNA is a single-stranded helix, unlike the double-stranded structure of DNA found in bacteria and higher organisms.

Antoine Lavoisier was a renowned French chemist and a key figure in the 18th-century chemical revolution. He developed an experimental theory on the chemical reactions of oxygen and co-authored a modern system for naming chemical substances. His groundbreaking work in chemistry included formulating the law of conservation of mass and proposing a theory on the oxidation of substances in 1777, earning him the title of the father of modern chemistry.

Lavoisier began his scientific career in 1768 when he was admitted to the prestigious French Academy of Sciences in Paris. He believed that matter is neither created nor destroyed in chemical reactions. Through his meticulous experiments, he demonstrated this principle by proving that mass is conserved in chemical reactions, a fundamental concept of Enlightenment-era science. Achieving this insight took years of work and the assistance of others.

In the annals of chemistry, Lavoisier is celebrated as the leader of the 18th-century chemical revolution and a founding figure of modern chemistry. His work was marked by careful investigation and quantitative analysis, laying the groundwork for chemistry as a true science. By 1785, his new theory of combustion had gained wide acceptance, and the movement to redefine chemistry based on its principles was underway.

Ahmed Zewail was an Egyptian-American chemist who won the Nobel Prize in Chemistry in 1999 for pioneering the study of chemical reactions using ultra-fast laser pulses on a timescale that revealed how these reactions occur. Zewail's graduate research on new spectroscopic techniques, including optical detection of resonance, was done with Robin Hochstrasser at the University of Pennsylvania. His postdoctoral work involved studying bonding in multi-dimensional systems and energy transfer in solids, working with Charles B. Harris at the University of California, Berkeley.

During the 1980s and 1990s, Ahmed Zewail led his team in conducting groundbreaking experiments on femtochemistry—the study of chemical reactions in real-time using pulses of light that lasted less than a picosecond (one trillionth of a second). This ultra-short timescale is the domain of molecular-level chemical reactions and atomic motions. His work earned him the Nobel Prize in Chemistry in 1999. Before the advent of such high-speed lasers in the 1970s, chemists' understanding of molecular dynamics in excited states was vastly different from what it is today.

Through these experiments, his team clarified the dynamics of chemical reactions, identified molecular pathways, and illuminated the quantum mechanical evolution of atoms within molecules. One of their signature tools was the pump-probe experiment, where the first pulse (the pump) initiates a chemical reaction, and the second pulse (the probe) tracks the subsequent events. This technique allowed Zewail's team to capture the transient oscillations, rearrangements, and products of reactions. After receiving the Nobel Prize, Zewail shifted his research focus to developing a new form of electron microscopy that uses ultra-fast electron pulses to study reactions in space and time at the atomic scale.

Dmitri Mendeleev was a Russian chemist and inventor who revolutionized the field of chemistry by creating the periodic table of elements, a breakthrough that allowed him to predict the properties of elements yet to be discovered. Sponsored by a government scholarship, he spent two years studying at the University of Heidelberg. Instead of closely collaborating with renowned chemists like Robert Bunsen, Emil Erlenmeyer, and August Kekulé, Mendeleev set up his own laboratory in a private apartment.

He also discovered the concept of critical boiling temperature. Mendeleev observed that when elements were arranged in increasing order of atomic mass, their properties displayed a periodic pattern. In his 1871 version of the periodic table, he left gaps where he believed unknown elements would fit. He even predicted the properties of three such elements. Later discoveries of elements that matched his predictions, particularly gallium, scandium, and germanium, solidified his reputation as the founder of the periodic law.

His new periodic law was first presented to the Russian Chemical Society in March 1869, declaring that “when elements are arranged by their atomic mass, they exhibit a clear periodicity of properties.” Mendeleev's law enabled him to construct a system for organizing all 70 known elements at the time. He also suggested corrections to the accepted atomic weights of several elements and predicted the positions of yet-to-be-discovered elements along with their potential properties. Initially, Mendeleev’s periodic system was met with skepticism. However, with the later confirmation of elements he had predicted, the periodic table gained widespread acceptance and became a cornerstone of modern chemistry.

Marie Curie was a Polish-born chemist and physicist who pioneered the study of radioactivity. She was the first person ever to receive two Nobel Prizes in different fields—Chemistry and Physics. In 1903, she shared the Nobel Prize in Physics with Henri Becquerel and her husband Pierre Curie for their work on radioactivity. Then, in 1911, she became the only person to receive the Nobel Prize in Chemistry for her discovery of the elements radium and polonium. Curie remains the only woman to have won Nobel Prizes in two different scientific disciplines.

During World War I, Marie Curie, with the help of her daughter Irène, contributed significantly to the development of mobile X-ray units. One of her key achievements was realizing the need to collect high-intensity radioactive sources, which had wide applications in medicine and research. Sadly, just months after this discovery, she passed away from aplastic anemia, a condition caused by prolonged radiation exposure. Marie Curie’s ashes are now enshrined in the Panthéon in Paris, a rare honor for a woman, awarded for her remarkable achievements. Her office and laboratory at the Radium Institute are preserved as the Curie Museum.

The practical applications of radium and polonium have been groundbreaking, enabling the development of heat sources for warmth and power, as well as serving as crucial materials for batteries in electronic devices and in nuclear energy production.

Louis Pasteur was a French chemist and microbiologist who made groundbreaking contributions to both medicine and chemistry. He is best known for developing vaccines for rabies and anthrax, which dramatically reduced mortality rates. Pasteur's discoveries on vaccination, fermentation, and pasteurization laid the foundation for modern microbiology. His name is honored worldwide, with numerous research institutes named after him in various languages. Pasteur's research in bacteriology greatly influenced French industries, particularly in wine production, for which he was awarded a prestigious honor by Emperor Napoleon III for his contributions.

Pasteur's path to fame began with his work on the crystallography of tartar, which led to advancements in the study of racemic acid. His excitement over this discovery was so great that he ran out of his laboratory to share the news with the first person he met. The most significant of his chemical contributions was his research into molecular asymmetry and racemization. Pasteur's renowned work in microbiology, particularly in the study of souring milk and the development of pasteurization to preserve milk, solidified his place in history. His proof of the germ theory and the development of vaccines against infectious diseases were monumental achievements in science.

John Dalton was an English meteorologist, chemist, and physicist renowned for his groundbreaking contributions to atomic theory and his studies on color blindness. Dalton gained hands-on experience in meteorology, using tools to measure weather and record daily observations, a practice he maintained throughout his life. He was particularly interested in the properties and behavior of gases.

In 1808, Dalton introduced the atomic theory to explain the law of conservation of mass and the law of definite proportions in chemical reactions. His atomic theory is the foundation of modern chemistry, and it was built on five key hypotheses:

• All matter is made up of atoms.
• Atoms of the same element have identical properties and structures.
• Atoms cannot be created, destroyed, or divided into smaller parts.
• Atoms of different elements combine in fixed ratios to form compounds.
• During chemical reactions, atoms combine, separate, or rearrange.

Dalton's atomic theory not only clarified these laws but also laid the groundwork for future atomic theories. He passed away from a stroke, and his funeral was regarded with the utmost respect, akin to a state funeral in his hometown.