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Mystery Periodic Table

Scientists who contributed to the
Anaximander, Empedocles, Thales, Anaximenes, Heraclitus
Ancient Greeks of the 6th and 5th c. BC -- taught the idea of "four elements" -- fire, air, water, earth.
Democritus (5th c BC), Epicurus (4th c AD), Lucretius (1st c BC)
"Atomos" -- thought everything that existed reduced to uncuttable bits of matter called "atoms".
thought fire, air, water and earth were bodies made of elements of moist, dry, hot, and cold
Roger Bacon
friar of13th century England, He is most widely known as being one of the first people to use experimental methods in alchemy - the root of modern chemistry
a person versed in the art of alchemy, an ancient branch of natural philosophy that eventually evolved into chemistry and pharmacology.
A chemical philosophy having as its asserted aims the transmutation of base metals into gold, the discovery of the panacea, and the preparation of the elixir of longevity.
Jan Baptist van Helmont
early modern period Flemish chemist, physiologist, and physician.....discoverer of CO2, remembered today largely for his ideas on spontaneous generation, his 5-year tree experiment, and his introduction of the word "gas" (from the Greek word chaos) into the vocabulary of scientists.
Boyle, Sir Robert (1637-1691)
Formulated fundamental gas laws. First to conceive the possibility of small particles combining to form molecules; distinguished between compounds and mixtures; studied air and water pressures, desalination, crystals and electrical phenomena.
Priestley, Joseph (1733-1804)
Discovered oxygen, carbon monoxide and nitrous oxide.
Johann J. Becher(1700's)
believed in a substance called phlogiston. When a substance is burned, phlogiston was supposedly added from the air to the flame of the burning object. In some substances, a product is produced. For example, calx of mercury plus phlogiston gives the product of mercury.
Charles Coulomb (1700's)
discovered that given two particles separated by a certain distance, the force of attraction or repulsion is directly proportional to the product of the two charges and is inversely proportional to the distance between the two charges.
Priestley, Joseph (1733-1804)
Discovered oxygen, carbon monoxide and nitrous oxide. -- heated calx of mercury, collected the colorless gas and burned different substances in this colorless gas. ...called the gas "dephlogisticated air", but it was actually oxygen.
Antoine Lavoisier
disproved the Phlogiston Theory. He renamed the "dephlogisticated air" oxygen when he realized that the oxygen was the part of air that combines with substances as they burn. Because of Lavoisier's work, Lavoisier is now called the "Father of Modern Chemistry".Discovered nitrogen; studied acids and described composition of many organic compounds.
Dalton, John (1766-1844)
The first great chemical theorist; proposed atomic theory (1807); stated law of partial pressure of gases. His ideas led to laws of multiple proportions, constant composition and conservation of mass.
Avogadro, A. (1776-1856)
Proposed principle that equal volumes of gases contain the same number of molecules. The number (6.02 x 1023 for 22.41 litres of any gas) is a fundamental constant that applies to all chemical units.
Davy, Sir Humphry (1778-1829)
Laid foundation of electrochemistry, studied electroysis of salts in water and other electrochemical phenomena; isolated Na and K.
Gay-Lussac, J.L. (1778-1850)
Discovered boron and iodine, studied acids and bases and discovered indicators (litmus); improved production method for H2SO4, did basic research on behavior of gases versus temp and on the ratios of gas volumes in chemical reactions.
Berzelius J.J. (1779-1850)
Classified minerals chemically; discovered and isolated many elements (Se, Th, Si, Ti, Zr); coined the terms isomer and catalyst; noted existence of radicals; anticipated discovery of colloids.
Mendeléev, D.I. (1834-1907)
Discovered periodicity of the elements and compiled the first Periodic Table.