The Men & Exp. I
Aristotle
Who believed the Earth was composed of 4 elements; earth, wind, fire, and water.
Gold Foil Experiment
What experiment demonstrated the existence of a nucleus surrounded by orbiting electrons?
Electron
What is the subatomic particle that has a negative charge and no discernible mass?
number of protons and neutrons
What is the mass number?
one proton & one electron
What is hydrogen?
The name of the most un-reactive elements on the periodic table to the right.
What are the noble gases?
What happens when the nucleus throws off smaller parts of itself?
What is radioactivity?
Rutherfod
Who is the scientist who proposed the atom with a positive nucleus with orbiting negative electrons?
Matter can not be created nor destroyed, only transformed.
What is the Law of Conservation of Mass?
neutron
What is the subatomic particle located in the nucleus and having no charge?
atomic number
What is number of protons (and electrons) in an atom?
eight protons & eight electrons & eight neutrons
What is oxygen?
Groups 3 through 12 on the periodic table.
What are the transition metals?
The least dangerous of the three types of emitted radiation, represented by a helium atom in nuclear equations.
What is an alpha particle?
J.J. Thomson
Who proposed the plum pudding model of the atom and discovered electrons?
cathode ray tube
What is the experiment that proved the existence of electrons?
proton
What is the subatomic particle with a positive charge and mass of 1?
The nomenclature of using the mass number (superscript) and the atomic number (subscript) along with the symbol of the element.
What is nuclear notation?
two protons & two neutrons in the nucleus
What is helium?
The most violently reactive metals on the periodic table (to the left).
What are the Alkali metals?
The strongest type of radiation that is dangerous to humans.
What is gamma radiation?
Neils Bohr
Who modified the atomic model to place electrons in levels based on their energy (rings or spheres)?
Matter is made of atoms which are solid, homogeneous, indestructible, and indivisible.
Who is Democritus?
protons and neutrons
What is the nucleus of an atom?
The average mass of all the isotopes present in nature of an atom.
What is the atomic mass (or atomic weight)?
17 protons and 18 neutrons
What is chlorine?
Group 2 on the periodic table.
What are the Alkaline Earth Metals?
The type of radiation represented as a high speed electron with a charge of -1 in nuclear equations.
What is a beta particle?
John Dalton
Who is the author of the first modern atomic model?
The first to use an analytical balance to measure reactants and products in experiments.
Who was Antoine Lavoisier?
AMU (atomic mass unit)
What is the unit used to label the masses of subatomic particles?
isotopes
What are atoms with the same number of protons but differing in the number of neutrons?
The number of neutrons in Uranium 235.
What is 143 neutrons?
Group 17 on the periodic table.
What are the halogens?
The name of the Russian reaction that had a melt down in the 1980s.
What is Chernobyl?