Melting (Melting Point)                                 Element
    It is the change of state from solid to               An element is a substance consisting of
     liquid.                                                atoms which all have the same number of
    Melting Point : It is the temperature at               protons - i.e. the same atomic number.
     which a solid melts. It decreases in the              It can only be changed into other elements
     presence of impurity. The melting point of             using nuclear methods.
     ice is 0°C or 32°F.                                   In the earth"s crust, oxygen (47 %) is the
                                                            most abundant element, followed by
Evaporation (Boiling Point)                                 silicon (28 %) and aluminum (8 %).
    It is the change of state from liquid to gas.         There are 118 elements that have been
    Boiling Point : It is the temperature at               identified, of which the first 94 occur
     which a liquid evaporates. Boiling point of            naturally on Earth with the remaining 24
     water at normal condition is 100°C or                  being synthetic elements.
     212°F.                                                On the Periodic Table, there are three
                                                            major types of elements known as Metals,
Freezing Point                                              Non-Metals, and Metalloids.
                                                           Metals are generally shiny, malleable, and
It is the change of state from liquid to solid.             hard. Metals are also good conductors of
Water freezes at 0°C or 32°F.                               electricity. e.g. Gold, Silver, Iron, etc.
Chemical Classification of Matter                          Non-metals do not conduct heat or
                                                            electricity very well. Non-metals are
Pure Substance                                              typically brittle and are not easily molded
                                                            into shapes. e.g. Hydrogen, Carbon, etc.
    A material that is composed of only one               Metalloids share characteristics of both
     type of particle; examples of a pure                   metals and non-metals and are also called
     substance include gold, oxygen and water.              semimetals. Metalloids are typically semi-
    It can be either an element or a compound,             conductors, which mean that they both
     but the composition of a pure substance                insulate and conduct electricity. e.g.
     doesn’t vary.                                          Silicon, Boron, etc.
    Atom is the smallest amount of an
     element. It is composed of a dense core                Elements with Atomic Numbers 113, 115,
     called the nucleus and a series of outer               117 and 118 were discovered in 2016.
     shells occupied by orbiting electrons. The             Named as Ununtrium (Uut), Ununpentium
     nucleus, composed of protons and                       (Uup),       Ununseptium        (Uus)      and
     neutrons, is at the center of an atom.                 Ununoctium (Uuo) respectively. These
     Protons have a positive electric charge                elements were discovered by Russian-
     while neutrons are neutral.                            American team of scientists at the Joint
    Molecule is two or more atoms that are                 Institute for Nuclear Research in Dubna
     chemically joined together. The diatomic               and Lawrence Livermore National
     molecules are (H2) Hydrogen, (N2)                      Laboratory in California.
     Nitrogen, (O2) Oxygen, (F2) Fluorine,
     (Cl2) Chlorine, (I2) Iodine and (Br2)