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Antoine Lavoisier
Antoine Lavoisier was a French chemist who became the father of modern day chemistry, through a conscious revolution. He demonstrated with careful measurements that transmutation of water to earth was impracticable, but that the residue observed from boiling water came from the container. He burnt phosphorus and sulfur in air, and proved that the elements weighed more than the original. However, the weight gained was lost from the air. Therefore he established the Law of Conservation of Mass. -
Joseph Proust
Joseph Proust was a French chemist who became known for helping prove the idea that every pure chemical compound consists of elements in a definite proportion. Today, scientists accept this idea as the law of constant proportions. In his day, chemists disagreed on whether the proportion of elements in a compound was definite. Claude-Louis Berthollet, an influential French chemist, debated Proust for years on the subject in the early 1800's. Chemists accepted Proust's evidence as correct by 1808. -
John Dalton
John Dalton was an English meteorologist who switched to chemistry when he saw the applications for chemistry of his ideas about the atmosphere. He proposed the Atomic Theory in 1803 which stated that all matter was composed of small inseparable particles termed atoms, atoms of a given element possess unique characteristics and weight, and three types of atoms exist: elements, simple molecules, and complex molecules. Dalton's theory was presented in New System of Chemical Philosophy. -
William Crookes
William Crookes was an English physicist who experimented with cathode ray tubes with Goldstein. In 1861, while conducting a spectroscopic examination of the residue left in the manufacture of sulphuric acid, he observed a bright green line which had not been noticed previously, and by following up the indication thus given he succeeded in isolating a new element, thallium, a specimen of which was shown in public for the first time at the exhibition of 1862. -
JJ Thomson
JJ Thomson, full name Joseph John Thomson, was a Britain physicist who in 1897 discovered the electron in a series of experiments designed to study the nature of electric discharge in a high-vacuum cathode-ray tube. In 1904 he suggested a model of the atom as a sphere of positive matter in which electrons are positioned by electrostatic forces. -
Max Planck
Max Planck was a German physicist who proposed the quantum of action, now known as Planck's constant h, explaining the pattern of light intensity emitted from a black body at any given frequency. His work appeared in its earliest form in a 1900 paper titled Zur Theorie der Gesetzes der Energieverteilung im Normal-Spektrum (On The Theory of the Law of Energy Distribution in the Continuous Spectrum), which formed the baseline for a new field of physics, quantum mechanics. -
Marie Curie
Marie Curie, originally Marie Sklodowska was a Polish physicist and chemist and one of the most famous scientists of her time. She and her husband, Pierre Curie, worked together studying radioactivity. During World War One Marie helped equip ambulances with x-ray equipment, which she herself drove to the front lines. The International Red Cross made her head of its radiological service and she held training courses for medical orderlies and doctors in the new techniques. -
Ernest Rutherford
Ernest Rutherford was a skilled experimentalist who was responsible for a remarkable series of discoveries in the fields of radioactivity and nuclear physics. He discovered alpha and beta rays, set forth the laws of radioactive decay, and identified alpha particles as helium nuclei. Most important, was that he hypothesized the nuclear structure of the atom. -
Albert Einstein
Albert Einstein was probably the most famous and accomplished scientist of all time. In 1905 Einstein wrote five scientific papers, including his most famous work, "Does the Inertia of a Body Depend upon its Energy Content?" This is the paper which concluded that any increase in energy (E) causes a corresponding increase in mass (m), and that these increases are related by the speed of light in a vacuum (c) squared — E=mc². In 1955 he died due to an enlargement of the heart. -
Niels Bohr
Niels Bohr was a Danish physicist who studied under J. J. Thomson and Ernest Rutherford, whose work was expanded by Bohr into a new theory on the structure of the atom in 1913. Bohr hypothesized that electrons travel in fixed orbits around the atom's nucleus, and further explained how electrons emit or absorb energy, work that earned him the Nobel Prize in Physics in 1922. Bohr's theory laborated and expanded by other physicists, formed the basis for the developing science of quantum mechanics. -
Erwin Schrödinger
Erwin Schrödinger was an Austrian physicist that won the Nobel Prize for Physics in 1933, for his 1926 introduction of Schrödinger's wave, the mathematical equation of wave mechanics that is still the most widely used piece of mathematics in modern quantum theory. He introduced his famous "Schrödinger's cat" paradox in a 1935 paper, "The present situation in quantum mechanics". The cat quandary was intended to show the irrationality of quantum physics. -
James Chadwick
James Chadwick was an English physicist who discoved the neutron during the investigation of beryllium disintegration in 1932. Three years after the discovery of the neutron, he was awarded the Nobel Prize in physics in 1935. As World War II broke out, Chadwick played a prominent role in the effort to create the atomic bomb as the leader of the British effort on the Manhattan Project. -
Louis de Broglie
Louis de Broglie was a French quantum physicist who introduced his theory of particle-wave duality in 1924. In his time, the wave and particle interpretations of light and matter were seen as being at odds with one another, but he suggested that these seemingly different characteristics were instead the same behavior observed from different perspectives. His theory helped explain how atoms, molecules, and protons behave, and he earned the Nobel Prize for Physics in 1929. -
Friedrich Hund
Friedrich Hund was a German physicist known for his work on the electronic structure of atoms and molecules. He helped introduce the method of using molecular orbital’s to determine the electronic structure of molecules and chemical bond formation. Hund taught and did research at German universities (Rostock, Leipzig, Jena, Frankfurt am Main, and Göttingen) exclusively, except for one year spent as a visiting lecturer at Harvard University. -
Werner Heisenberg
Werner Heisenberg was a German physicist who studied under Max Born, David Hilbert, and Arnold Sommerfeld, and won the Nobel Prize for Physics in 1932. Of more lasting impact was his 1927 uncertainty principle, which states that it is impossible to accurately measure both position and momentum (energy and time) concurrently, and that the more precisely we know an object's position the less precisely we can know its momentum, and vice versa. -
Murray Gell-Mann
Murray Gell-Mann is an American theoretical physicist who proposed the Eightfold way, a new classification system for baryons (heavy subatomic particles) to explain the almost infinitely complex kinds of particles in collisions involving atomic nuclei. In 1964 he discovered the quark, omega-minus particles believed to be fundamental building blocks of neutrons, protons, and matter itself. This discovery strengthened evidence for the Eightfold Way, and got him the Nobel Prize for Physics in 1969.
