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atomic scientists 1
atomic scientists 2
atomic scientists 3
atoms 1
atoms 2
100
Discovered oxygen and carbon dioxide
who is Joseph Priestley?
100
Developed modern atomic theory
who is John Dalton?
100
He is credited for the discovery of the electron and of isotopes, and the invention of the mass spectrometer.
who is J.J. Thomson?
100
protons are _________ charged particles
What is positively?
100
the sum of protons and neutrons in an atom
What is the mass number?
200
Father of modern chemistry; He stated the first version of the law of conservation of mass,[2] recognized and named oxygen (1778) and hydrogen (1783); helped construct the metric system, wrote the first extensive list of elements, and helped to reform chemical nomenclature. He discovered that, although matter may change its form or shape, its mass always remains the same.
who is antoine lavoisier?
200
stated that gases are composed of molecules, and these molecules are composed of atoms; the relative molecular mass of a gas can be calculated from the mass of sample of known volume; developed this hypothesis after Joseph Louis Gay-Lussac had published in 1808 the his law on volumes (and combining gases);
who is amedeo avogadro?
200
He is known mostly for two laws related to gases, and for his work on alcohol-water mixtures, which led to the degrees Gay-Lussac used to measure alcoholic beverages in many countries
who is Joseph Louis Gay-Lussac?
200
no charge
What is a neutron?
200
an unstable atom is an atom whose nucleus can change its composition
What is radioactive?
300
the theory of structure provided dramatic new clarity of understanding, and a reliable guide to both analytic and especially synthetic work. As a consequence, the field of organic chemistry developed explosively from this point; idea of assigning certain atoms to certain positions within the molecule, and schematically connecting them using what he called their valences; benzene ring structure
who is august kekule?
300
He is credited as being the creator of the first version of the periodic table of elements. Using the table, he predicted the properties of elements yet to be discovered.
who is dmitri mendeleev?
300
He is probably best remembered today for his discoveries of several alkali and alkaline earth metals, as well as contributions to the discoveries of the elemental nature of chlorine and iodine. Davy was a pioneer in the field of electrolysis using the voltaic pile to split up common compounds and thus prepare many new elements. He went on to electrolyse molten salts and discovered several new metals, especially sodium and potassium, highly reactive elements known as the alkali metals.
who is humphry davy?
300
negatively charged particles
What is an electron?
300
atoms that have the same number of protons but have different numbers of neutrons, atoms of the same element that differin weight
What are isotopes?
400
He investigated emission spectra of heated elements, and with Gustav Kirchhoff discovered caesium (in 1860) and rubidium (in 1861). The Bunsen-Kirchhoff Award for spectroscopy is named after Bunsen and Kirchhoff
who is robert bunsen?
400
became known as the father of nuclear physics; Rutherford performed his most famous work after he received this prize. In 1911, he postulated that atoms have their positive charge concentrated in a very small nucleus,[3] and thereby pioneered the Rutherford model, or planetary, model of the atom; He is widely credited with first splitting the atom in 1917, and leading the first experiment to "split the nucleus" in a controlled manner by two students under his direction, John Cockcroft and Ernest Walton in 1932.
who is ernest rutherford?
400
known for the discovery of the covalent bond; In 1926, Lewis coined the term "photon" for the smallest unit of radiant energy; lewis dot diagrams showing bonding of atoms.
who is gilbert n. lewis?
400
when an atom becomes a charged particle due to the difference in number between the protons and neutrons
What is an isotope?
400
how to tell the difference between isotopes of an element?
What is the mass number?
500
Her achievements include the creation of a theory of radioactivity (a term she coined[2]), techniques for isolating radioactive isotopes, and the discovery of two new elements, polonium and radium. Under her direction, the world's first studies were conducted into the treatment of neoplasms (cancers) using radioactive isotopes
who is marie curie?
500
He is mainly known for simplifying the production of celluloid, the first industrial plastic
who is john wesley hyatt?
500
The invention of Bakelite marks the beginning of the Age of Plastics[2]. Bakelite was made from phenol (then known as carbolic acid) and formaldehyde. These can be mixed, heated, and then either molded or extruded; Bakelite was the first plastic invented that held its shape after being heated. Radios, telephones and electrical insulators were made of Bakelite because of its properties of insulation and heat-resistance. Soon it penetrated nearly all branches of industry
who is leo baekeland?
500
the number of protons in an atom
What is atomic number?
500
percent of mass in nucleus
how much is 98%?