Term | Definition |
Periodic Table | a table illustrating the periodic system, in which the chemical elements, formerly arranged in the order of their atomic weights and now according to their atomic numbers |
Element | cannot be separated into simpler substances by chemical means |
Element Symbol | code for a chemical element |
Atomic Number | the number of positive charges or protons in the nucleus of an atom of a given element |
Atomic Mass | the mass of an atomic particle, sub-atomic particle, or molecule |
Period | a length or portion of time. |
Group | is a column of elements in the periodic table of the chemical elements. There are 18 numbered groups in the periodic table |
Family | is a column of elements in the periodic table of the chemical elements. There are 18 numbered groups in the periodic table |
Chemical Formula | a way of expressing information about the proportions of atoms that constitute a particular chemical compound |
Metals | good electrical and thermal conductor |
Nonmetals | element that doesn't have the characteristics of metal including the ability to conduct heat or electricity |
Metaloids | properties are intermediate between those of metals and solid nonmetals |
Noble Gasses | any of the seven chemical elements that make up Group 18 (VIIIa) of the periodic table |
Reactivity | the relative capacity of an atom, molecule |
Dmitri Mendejeev | Russian Chemist that helped develop the periodic law |
Trend | provide chemists with an invaluable tool to quickly predict an element's properties |
Energy level | fixed amount of energy |
Valence Electrons | the electrons in the outer shell of an atom. The valence electrons are the ones involved in forming bonds to adjacent atoms |
Chemical property | any of a material's properties that becomes evident during, or after, a chemical reaction |
PysycalProperty | any property that is measurable, whose value describes a state of a physical system |