Atoms - Molecules - Ions. Molecular Basis of Substances. Substances. Compounds. Elements. Atoms. Molecules. Molecules. Ion. Ions. Periodic Table of the Elements. Hydrogen – 1 proton per atom. Carbon – 6 protons per atom. Elements.
Molecular Basis of Substances
Put elements in rows by increasing atomic weight.
Put elements in columns by the way they reacted.
He left blank spaces for what he said were undiscovered elements. (Turned out he was right!)
He broke the pattern of increasing atomic weight to keep similar reacting elements together.Dmitri Mendeleev: Father of the Table
Metals – Nonmetals - Metalloids
Metals: A material that has a characteristic luster or shine
and that is a relatively good conductor of heat and
electricity (Metal oxides react with water to form
bases and are located on the left side of the table)
Nonmetals: A element that does not exhibit the properties
of a metal. (Nonmetal oxides react with water to
form acids and are on the right side of the table)
Metalloids: Elements with properties intermediate
between those of metals and nonmetals.
Metals never occur in nature as pure elements
Alkaline Earth metals
allotropes of carbon
Greek for “salt-forming”
How many protons, neutrons and electrons are found in an atom of
Atomic number = protons and electrons
There are 55 protons and 55 electrons
Mass number = sum of protons and neutrons
133 – 55 = 78
There are 78 neutrons