This document provides an overview of models and the structure of matter. It discusses how models are simplified representations of reality used in science, architecture, and business. Matter is composed of tiny particles that are in constant motion. The motion of particles is related to temperature and the state of matter. Solids, liquids, and gases differ in how freely particles can move and how strongly they attract each other. Elements are the fundamental units that make up compounds and cannot be broken down further chemically. The periodic table organizes elements according to their properties and atomic structure. Elements can have different isotopes that vary in neutron number. Molecules form when atoms bond together via sharing or exchanging electrons.

1. Textbook: Baker

2. Section 2.1

3.  A model is a simplified approximation of
reality.
◦ Architects build models before the actual
construction
◦ Business owners build models
 Science models are simplified but, useful as a
representation of what the structure will be
like
◦ Models are not always physical entities
◦ Some could simply be a set of ideas

4.  All matter is composed of tiny Particles
 These Particles are in constant motion
 The amount of motion is related to
temperature. Increased temperature
represents increased motion
 Solids, gases, and liquids differ in the
freedom of motion of their particles and in
how strongly the particles attract each other.

5.  Particles of a solid can be pictured as tiny
spheres held closely together
 When a solid is heated, the average speed of
the moving particles increases.
 Faster-moving particles collide more
violently, causing each particle to push its
neighboring particle far away
 Therefor the increase in temperature usually
causes the solid to expand

7.  Particles in a liquid are still close together
but, have more empty space between them
than in a Solid
 Liquids normally expand to fill a slightly
larger volume
 Attractions between them keep then a certain
distance apart
 Freedom of movement allows liquids to take
the shape of their container

9.  Particles of a gas are much father apart than
a solid or liquid
 According to the model each particle in a gas
moves freely in a straight-line path until it
collides with another particle
 Particles are moving very fast and normally
bounce off each other and continue on their
own path

11. Section 2.2

12.  Scientific Investigation
◦ Are all the particles in a solid, liquid, or gas
identical?
◦ What are the particles made of?
 Materials
◦ Glass of Water
◦ Dissolved table salt

13. 1. Heating can separate the salt and water
(Distillation)
◦ The water will evaporate thus, leaving the salt
◦ Using the distillation apparatus water vapor will
be cooled and placed into a separate container
2. Run electric current through water and
break down into Hydrogen gas and Oxygen
Gas
3. Run electric current through melted dry salt
and break down into Sodium metal and
Chlorine gas

14.  Salt water has been broken down into 4
elements or building blocks of matter
◦ Elements –are substances that cannot be chemically
converted into simpler ones

15.  Water consist of
◦ Hydrogen
◦ Oxygen
 Salt consist of
◦ Sodium
◦ Chlorine
 These are both chemical compounds (covered
in Chapter 3)
 The mixture of the two are known as a
solution (covered in Chapter 4)

17.  There are current 114 elements
◦ 24 are not naturally found on Earth
 2-3 might exist in Stars
◦ Some elements found in nature are Unstable
 These elements exist for a limited time and then turn
into other elements via radioactive decay
◦ Of the 83 stable elements found in nature, many
are rare and will not be mentioned in this text

18.  Each element is known by name and a symbol
 They are named in a variety of ways
◦ The elements Francium and Californium were
named to honor the places where they were
discovered.
◦ Some reflect the source from which the element
was first isolated
 Hydrogen came from the Greek words water(hydro)-
forming(genes)
◦ Some elements are named for their appearance
 Idos means violet in Greek

19.  Symbols are also chosen in a variety of ways
◦ Some are the first letter of an elements name
 C represents Carbon
 When two letters are used the first is capitalized the
second is lowercase
 Cl is chlorine and Co is cobalt
◦ Some symbols use the Latin names for the elements
 Na is sodium (Latin natrium)
 Au is gold (Latin aurum) means shining dawn
 Most recent are not named yet are given
temporary names and three letter symbols

21. Section 2.3

23.  Arranged in groups or families that have
similar characteristics
◦ They are in columns
◦ They are commonly referred to as Groups or
Families
◦ Groups are numbered 1-18
◦ Groups A or B
 This convention is explained and illustrated better on
the following slide

26.  Properties
◦ Metals have a shiny metallic luster.
◦ Metals conduct heat well and in the solid form
conduct electric currents.
◦ Metals are malleable, which means they are capable
of being extended or shaped by the blows of a
hammer.

27.  Characteristics
◦ Some are gases at room temperature and pressure
◦ Some are solids
◦ Only one is a liquid
◦ They do not have the characteristics listed
previously for metals

28.  Characteristics
◦ Have some but not all the characteristics of metals
 Metalloids include:
◦ Boron
◦ Silicon
◦ Arsenic
◦ Tellurium
◦ Astatine
◦ Germanium
◦ Antimony
◦ Polonium

30. 

31. Section 2.4

32. 

33. 

35. 

37.  When an element has two or more atoms,
each with the same number of protons but a
different number of neutrons, the different
species of element are called isotopes.

38.  Atomic number is the number of protons in
an uncharged atom
 Atomic mass is the sum of protons and
neutrons in an atom
*The Atomic number of an isotope is the same
but, not the mass number because of the
difference between the number of neutrons. To
specify the different isotopes the mass number
with follow the symbol for the element.

39. 

40. 

41. Section 2.5

42.  Covalent bond- the
sharing of electrons
 Molecules-
uncharged collection
of atoms
 Hydrogen molecules
contain two atoms;
which make them
Diatomic
*Notice the prefix Di indicates
there are two

43. 

48. 

50.  For review assignment Click Here