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447 BCE
Plato
Plato's most famous work is the Republic, which details a wise society run by a philosopher. He is also very famous for his dialogues. -
400 BCE
Democritus
Democritus' atomic theory states that all matter is composed of tiny, indivisible particles called atoms which are constantly moving through empty space, and the different properties of matter arise from the varying shapes and sizes of these atoms; -
384 BCE
Aristotle
Aristotle was the first real scientist in history and one of the greatest philosophers of all time. He recognized the many scientific disciplines and investigated their connections, as well as making groundbreaking contributions to all branches of philosophy and science and creating the area of formal logic. -
Robert Boyle
The relationship between a gas's pressure and volume, sometimes referred to as "Boyle's Law," which asserts that, when a gas's temperature stays constant, its volume falls as its pressure rises, is what made Robert Boyle most famous -
The Alchemists
Alchemists made significant discoveries in the field of chemistry, including isolating elements like antimony, arsenic, and zinc, developing experimental techniques like distillation, and inventing laboratory tools like flasks and bellows -
John Dalton
John Dalton was an English chemist, physicist, and meteorologist, best known for introducing the atomic theory into chemistry and for his work on human optics. He introduced the atomic theory into chemistry and for his work on human optics. -
Newlands Law of Octaves
The law of octaves is a generalization that states that when chemical elements are arranged in order of increasing atomic weight, the properties of the eighth element are similar to the properties of the first element. -
Mendelee's Pd. Table
Mendeleev's Periodic Table is primarily known for its innovative arrangement of elements based on their atomic mass, which allowed him to predict the existence and properties of yet undiscovered elements by leaving gaps in the table for them, a feature that significantly validated his theory and the periodic law. -
Discovery of Radioactivity
French physicist Henri Becquerel is credited with discovering radioactivity in 1896 when he by chance discovered that uranium salts release a penetrating radiation that can be picked up on a photographic plate. -
Planck's Quantum Theory of Light
Planck's Quantum Theory of Light states that light is not emitted or absorbed as a continuous wave, but rather in discrete packets of energy called "quanta" or "photons," meaning that light can only gain or lose energy in specific, fixed amounts, with the energy of each photon directly proportional to its frequency -
Plum Pudding Model
In order to balance the electrons' negative charges, JJ Tompson came up with "plum pudding model" because it had positively charged pudding around negatively charged plums. -
Photoelectric Effect
Heinrich Hertz found the process by which free electrons are emitted from the metal surface by the application of light -
Rutherford's Gold Foil Experiment
The structure of the atom was discovered by the Rutherford gold foil experiment. Rutherford and his students utilized a tube with a phosphorescent screen to determine the alpha particles' final destination after firing positively charged alpha particles through cold foil -
Bohr's Planetary Model
Niels Bohr came up with this scientific representation of the atom in which electrons travel in set, circular routes known as energy levels around the nucleus -
Robert Millikan
By demonstrating that electric charge is quantized and exists in discrete units through his well-known "oil drop experiment," Robert Millikan made the most important discovery that helped us understand the fundamental nature of electricity and the atom: the precise measurement of the charge of a single electron. -
Mosley's Atomic Numbers
Moseley's atomic numbers refer to the concept that the atomic number of an element, which is the number of positive charges (protons) in its nucleus, is the fundamental property that should be used to arrange elements on the periodic table, rather than their atomic mass -
Discovery of the Proton
This discovery proved by Ernest Rutherford that the nucleus of a hydrogen atom is present in the nuclei of all other atoms. -
Schrodinger Equation
The Schrödinger Equation is considered a groundbreaking discovery in physics because it provides the fundamental mathematical framework for describing the behavior of particles in the quantum realm -
Heisenberg Uncertainty Principle
Formulated by the German physicist and Nobel laureate Werner Heisenberg in 1927, the uncertainty principle states that we cannot know both the position and speed of a particle, such as a photon or electron, with perfect accuracy -
Discovery of the Neutron
The discovery of the neutron refers to the scientific finding by physicist James Chadwick, who proved the existence of a neutral particle within the atomic nucleus.