Definitions Flashcards
Atom
The smallest particle of matter that contains a nucleus and is electrically neutral
Atomic Number
The number of protons
Mass Number
No. Protons + No. Neutrons
Molecule
Two or more atoms that are covalently bonded
Element
A substance made from atoms that all have the same atomic number
Compound
A pure substance made of different types of atoms that are chemically bonded together
Mixture
Two or more substances that are not chemically combined
Ion
An atom that has gained an electrical charge by either losing or gaaining one or more valence electrons
Isotopes
Two or more atoms of the same element that have different numbers of neutrons. They are chemically identical because they have the same number of valence electrons
Excited state
When an electron temporarily occupies an energy state greater than its ground state.
Ground state
The lowest state of energy for that atom
Electronic configuration
1s 2s 2p 3s 3p 4s 3d
Nano meters to meters
1 nanometer = 10^-9m
