1.
Acid: Solution that contains hydrogen ions (H+)
2.
Atom: Smallest particle of an element, having all the characteristics of that element; the basic building block of matter, consisting of protons, neutrons, and electrons
3.
Atomic Mass: Average of the mass numbers of the isotopes of an element
4.
Atomic Number: Number of protons contained in an atom's nucleus
5.
Base: Solution that contains hydroxide ions (O-)
6.
Chemical Bonds: Force that holds the atoms of elements together in a compound
7.
Chemical Reaction: Change of one or more substances into other substances
8.
Compound: Substance composed of atoms of two or more different elements that are chemically combined
9.
Condensation: Process by which a cooling gas changes into a liquid and releases thermal energy
10.
Covalent Bond: Attraction of two atoms for a shared pair of electrons that holds the atoms together
11.
Crystalline Structure: Regular geometric pattern of particles in most solids, giving a solid a definite shape and volume
12.
Electron: Tiny atomic particle with little mass and a negative electrical charge that surrounds the nucleus in energy levels
13.
Element: Natural or artificial substance that cannot be broken down into simpler substances by physical or chemical means
14.
Energy Level: Represents the area in an atom where electrons are most likely to occur
15.
Evaporation: Vaporization—change of state, involving thermal energy
16.
Glasses: Solid that consists of densely packed atoms with a random arrangement and lacks crystals or has crystals that are not visible
17.
Ion: Electrically charged atoms or groups of atoms
18.
Ionic Bond: Attractive force between two ions with opposite charge
19.
Isotopes: Atoms of the same element that have different mass numbers and the same chemical properties
20.
Mass Number: Combined number of protons and neutrons in the nucleus of an atom
21.
Molecule: Combination of two or more atoms joined by covalent bonds
22.
Neutron: Tiny atomic particle that is electrically neutral and has about the same mass as a proton
23.
Nucleus: Positively charged center of an atom, made up of protons and neutrons and surrounded by electrons in energy levels
24.
Plasmas: Hot, highly ionized, electrically conducting gas
25.
Proton: Tiny atomic particle that has mass and a positive electrical charge
26.
Radioactivity: Spontaneous process of decay, or breaking apart, through which unstable nuclei emit radiation
27.
Solution: Homogeneous mixture whose components cannot be distinguished and can be classified as liquid, gaseous, solid, or a combination
28.
Sublimation: Process by which a solid slowly changes to a gas without first entering a liquid state
29.
Valence Electrons: Electron in an atom's outermost energy level
