Matter
the positively charged particles in a nucleus
proton
rows in the periodic table; elements in the same period have the same number of energy levels.
Period
the substance into which a solute is dissolved
Solvent
invisible, negatively charged particles that travel around the nucleus
Electron
generally have a shiny or metallic luster and are good conductors of heat and electricity. Metals are malleable (can be bent) and ductile (can be drawn into wires).
Metals
the transition of a substance from a solid directly to a gas without becoming a liquid first
Sublimation
an atom or molecule with a net electric charge (+/-) due to the loss or gain of one or more electrons
Ion
– the second group in the periodic table. They are not as reactive as the alkali metals, but still easily form bonds with most other elements; contain two electrons in their outermost shell
Alkaline Earth Metals
type of mixture where the substances are not evenly mixed
Heterogenous mixture
the positively charged, central part of an atom
Nucleus
the number of protons plus the number of neutrons an atom contains
Mass Number
the temperature at which a liquid changes to a solid state
Freezing point
the smallest unit of matter that has the properties of a chemical element
atom
matter that is made up of only one kind of atom
element
another name for a homogenous mixture
solution
uncharged particles in a nucleus
Neutron
group 17 in the periodic table, they react with metals to form salts
Halogens
the temperature at which a liquid changes to a gas (vapor).
boiling point
a spherical cloud of varying density surrounding the nucleus
Electron Cloud
elements that have some characteristics of metals and other characteristics of nonmetals
Metalloids
– the temperature at which a gas changes to a liquid state.
condensation point
atoms of the same element that contain different numbers of neutrons
Isotope
columns in the periodic table; elements in the same group have similar properties related to their structure and tend to form similar bonds
Group
the substance that is dissolved in a solution
solute
number located above an element’s chemical symbol that tells you the number of protons in the nucleus of each atom of that element
Atomic Number
the process whereby atoms or molecules in a liquid state (or solid state if the substance sublimes) gain sufficient energy to enter the gaseous state
evaporation
the first grouper in the periodic table. They are never found in nature uncombined because they are unstable, and they react fast to other elements; contain only one electron in their outermost shell
Alkali Metals
a substance produced when elements combine and whose properties are different from each of the elements in it.
compound
group 18 of the periodic table. They are the most stable due to having the maximum number of valence electrons their outer shell can hold
Metalloids
type of mixture where two or more substances are evenly mixed on a molecular level but are not bonded together
Homogenous mixture
substances that are made up of only one type of atom or molecule
pure substance