27 terms

Traner -Atoms and Elements

PH Explorer, Chapter 3, Atoms and elements
the center of an atom that contains most of the mass of the atom in the form of positive protons and negative neutrons
The positively charged (+) particle in the nucleus which determines what element this is an atom of. Example: 1 Proton is the element Hydrogen.
Dmitri Mendeleev
Russian scientist who discovered a logical pattern in the properties of the elements
atomic mass
the average mass of one atom of the element. The mass averages the common form and the isotopes. It is equal to the mass of the protons and the neutrons.
chemical symbol
usually consists of a one or two letter abbreviation of the element name
group or family
elements in a periodic table column that have similar properties
elements in a periodic table row and which change properties in a predictable pattern
a type of element that tends to be shiny, hard, malleable, ductile, and a good conductor
can be pounded into shapes
can be pulled into wire
a description of how easily and quickly an element combines with other elements and compounds
a type of element that lack most of the properties of metals
a type of element that has some of the characteristics of metals and some of the characteristics of nonmetals
when 2 or more ingredients are mixed but do not bond chemically
pure substance
made of one kind of matter and has definite properties, may be a single element or a compound
a substance that cannot be broken into smaller pieces
the "smallest piece of matter" that if broken into smaller pieces, loses its original properties
negatively charged particles; move around the outside of the nucleus
atomic number
the number of protons in an element's nucleus
periodic table
the chart that organizes the elements
atomic mass unit
special unit used for the mass of a subatomic particle
energy levels
the space around the nucleus in which the electrons travel
2, 8, 18
valence electrons
the electrons in energy level that is farthest from the nucleus; that helps determine which elements atom will bond with.
An atom with the same number of protons and a different number of neutrons from other atoms of the same element
an atom that has taken on or lost electrons to become negatively or positively charged instead of neutral
the ability of an object to allow heat and electricity to pass through it
the gradual wearing away of an element due to a chemical reaction