Download Mineral Chemistry #2

Minerals
 All minerals must have the following
characteristics:

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
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Naturally occurring by Earth’s processes.
Solid orderly crystalline structure
Definite Chemical Composition
Inorganic (salt IS a mineral, sugar is NOT
because it is organic)
Minerals
 A mineral is a naturally occurring,
inorganic solid with an orderly crystalline
structure and a definite chemical
composition.
Minerals
 Why are the following materials NOT
minerals?
 Chunk of Concrete
 Brass Ring
 Natural Gas
 Everything in the universe is made of
matter.
 Matter is found usually in three states:
 Solid
 Liquid
 Gas
 The building blocks of matter are
elements.
 An atom is the smallest particle of matter
that contains the characteristics of an
element.
 Atoms contain subatomic particles:
 Protons: Positively charged, found in the nucleus
 Electrons: Negatively charged, found outside of
the nucleus.
 Neutrons: No charge, found in the nucleus.
 Atomic number: The number of protons in
the nucleus of an atom.
 In a neutral atom, number of protons = number
of electrons.
 An element is a substance that cannot
be broken down into simpler substances
by physical or chemical means.
 There are currently more than 112 known
elements.
 92 occur naturally, others are created in
laboratories
 These elements are organized on the
periodic table of elements.
Mixture
 A mixture is a substance made by
combining two or more different materials
without a chemical reaction occurring
(the objects do not bond together).
The Periodic Table
(Pages 142-143 of your book)
Atomic
Number
Element
Name
1
H
Hydrogen
1.0079
Element
Symbol
Mass
Number
or
Atomic
Mass
 You will need:
 Graph paper, and a pen/pencil
 Using the periodic table:
 Make a line graph with atomic number
on the vertical axis and mass number
on the horizontal axis. Go from
elements 1-30.
 Answer the following:
 What does the graph show about the general
relationship between atomic number and
atomic mass?
 Are there any points on the graph that do not
follow the pattern?
 Does it make sense to organize the periodic
table by atomic mass or atomic number?
 An atom is the smallest particle of matter
that contains the characteristics of an
element.
 Atoms contain subatomic particles:
 Protons: Positively charged, found in the nucleus
 Electrons: Negatively charged, found in the outside
the nucleus.
 Neutrons: No charge, found in the nucleus.
 Atomic number: The number of protons in
the nucleus of an atom.
 In a neutral atom, number of protons = number of
electrons.
 Atoms of the same element always have
the same number of protons; but the
number of neutrons can vary.
 Atoms with the same number of protons
but different numbers of neutrons are
isotopes of an element.

(remember: Atomic Mass: Number of protons + neutrons)
 Example: Carbon-12 (99% of all carbon)
has 6 protons and 6 neutrons.
 Carbon-13 has 6 protons and 7 neutrons
 Carbon-14 has __
6 protons and __
8 neutrons
 Remember that in a neutral atom the
number of protons = number of
electrons.
 If there are more electrons than
protons, the overall charge of the
atom is negative.
 If there are more protons than
electrons, the overall charge of the
atom is positive.
Na
+1
Atomic Number: 11
Atomic Mass/Mass Number:
Charge: +1
Number of Protons: 11
Number of Neutrons: 12
Number of Electrons: 10
23
 A compound is a substance that consists
of two or more elements that are
chemically combined.
 When atoms combine to form compounds,
electrons are gained, lost, or shared.
 Ionic bonds form between positive and
negative ions. Electrons are transferred.
 Covalent bonds form when electrons are
shared.
 Metallic bonds form when electrons are
shared by metal ions.