8.5 A Atoms Flashcards
The smallest unit of an element that has all of the properties of that element and contains a nucleus within an electron cloud.
Atom
The tiny, very dense, positively charged region in the center of an atom that is made up of protons and neutrons.
Nucleus
All of the area inside an atom surrounding the nucleus where electrons are found.
Electron Cloud
A form of charge, designated negative, positive, or neutral (without charge) that is found on the subatomic particles that make up all atoms.
Electrical Charge
A positively charged subatomic particle of the nucleus of an atom that contributes to the mass of the atom.
Proton, p+
A subatomic particle of the nucleus of an atom that is without charge and contributes to the mass of an atom.
Neutron
A negatively charged subatomic particle of the electron cloud that is involved in the formation of chemical bonds.
Electrons
Particles that are smaller than the atom
Subatomic Particles
A shorthand notation that uses chemical symbols and numbers as subscripts to represent the type and number of atoms that are present in the smallest unit.
Chemical Formula
A symbolic representation of a chemical reaction in which both sides of the equation contain equivalent numbers of atoms of each element. The mass and charge must be balanced on both sides of the reaction.
Balanced Equation
The average mass of protons and neutrons in an element.
Atomic Mass
A conceptual model of the atom in which a small positively-charged nucleus is surrounded by planetary electrons.
Nuclear Model of the Atom
Numbers written in terms of a decimal number between one (1.0) and ten (10.0) multiplied by a power of ten. For example, the scientific notation for ten thousand four hundred ninety-two is 1.0492 X 10 (4)
Scientific Notation
