atoms Flashcards
Atoms
The smallest unit of an element that maintains the properties of that element
electron
A subatomic particle that has a negative charged
Nucleus
In physical science, an atom’s central region, which is made up of protons and neutrons
electron cloud
A region around the nucleus of an atom where electron are likely to be found
Proton
A subatomic particles that has a positive charge and that is found in the nucleus of an atom
Atomic mass number
A unit of mass that describes the mass of an atom or molecule.
Neutron
A subatomic particle that has no charged and that is found in.
Atomic number
The number of protons in the nucleus of an atom;the atomic number is the same for all atoms of an element.
Isotope
An atom that has the same number of protons (or the same atomic number) as other atoms of the same element do but that has a different number of neutrons (and thus a different atomic mass)
Mass number
The sum of the numbers of protons and neutrons in the nucleus of an atom
Atomic Mass
The mass of an atom expressed in atomic mass units
Democritus’s
The man who created an atom
John Dalton
A British chemist and schoolteacher who created an atomic theory.
Thomson
discovered electrons.
