3. 3
Why is Chemistry Important?
In Our Daily Lives
New Materials
New Pharmaceuticals
New Energy Sources
Food Supplies
Can you think of others?
5. 5
Why is Chemistry Important?
In Your Education
Help you learn to Gather and Organize
Information
Qualitative and Quantitative
Help you learn to find Patterns in
Information
Help you learn to Analyze Complex
Systems
Help you develop skills to Predict Future
Events based on Patterns of Behavior
Help you develop Problem-Solving Skills
6. 6
What is Chemistry?
The science that deals with the
materials of the universe and the
changes these materials undergo
The Central Science
Understanding most other fields of
science requires an understanding of
Chemistry
7. 7
Solving Problems Using a Scientific
Approach
Define the Problem
• Gather Information
Facts
Observations
Propose Solutions
• Organize Information and look for
Patterns
• Hypotheses
8. 8
Evaluate your Proposed Solutions
• Test your Patterns by using them to
Predict What Will Happen
• Experiments
Solving Problems Using a Scientific
Approach
9. 9
The Scientific Method
A process of studying natural
phenomena that involves making
observations, forming laws and
theories, and testing theories by
experimentation
10. The launch
of the space
shuttle gives
clear
indications
that
chemical
reactions
are
occurring.
Source:
NASA
11. 11
The Scientific Method
Make Observations
Qualitative Descriptions
Quantitative Measurements
Formulate Hypotheses
Possible Explanations for Observed
Characteristics or Behaviors
Perform Experiments
Test Hypothesis
12. 12
The Scientific Method
Repeat the process until we get a well-
tested explanation
Theory a set of assumptions put
forth to explain some aspect of the
observed behavior of matter
May need to be modified or discarded as
new information (observations) becomes
known
13. 13
The Scientific Method
While Experimenting we may Observe
the Same Behavior all the time, and
therefore be able to Predict this
Behavior will Always Occur in the
Future
Law a generally observed behavior
Without explanation as to why the
behavior occurs!
14. 14
The Difference Between a Theory and a
Law
Laws predict what will happen
Theories explain why something
happens
Which will also allow you to predict what
will happen!
16. **Only Memorize the most common elements. Calculations
can also be done on a calculator.
The Best Approach to Learning
Chemistry
Learn the Vocabulary of Chemistry
Definitions of Terms
How Common Vocabulary is Applied to Chemistry
Memorize Important Information**
Names, Formulas and Charges of Polyatomic Ions
Solubility Rules
Learn and Practice Processes
Systematic Names and Formulas
Dimensional Analysis
18. 18
Properties
Characteristics of the substance under
observation
Properties can be either
directly observable or
the manner something interacts with other
substances in the universe
19. 19
Universe Classified
Matter is the part of the universe that
has mass and volume
Energy is the part of the universe that
has the ability to do work
Chemistry is the study of matter
The properties of different types of matter
The way matter behaves when influenced
by other matter and/or energy
20. 20
Properties of Matter
Physical Properties are the characteristics of
matter that can be changed without changing
its composition
Characteristics that are directly observable
Chemical Properties are the characteristics
that determine how the composition of matter
changes as a result of contact with other
matter or the influence of energy
Characteristics that describe the behavior of
matter
21. 21
Classify Each of the following as
Physical or Chemical Properties
The boiling point of ethyl alcohol is
78°C.
Diamond is very hard.
Sugar ferments to form ethyl alcohol.
22. 22
Classify Each of the following as
Physical or Chemical Properties
The boiling point of ethyl alcohol is 78°C.
Physical property – describes inherent characteristic
of alcohol – boiling point
Diamond is very hard.
Physical property – describes inherent characteristic
of diamond – hardness
Sugar ferments to form ethyl alcohol.
Chemical property – describes behavior of sugar –
forming a new substance (ethyl alcohol)
23. 23
solid, liquid, gas
States of Matter
State Shape Volume Compress Flow
Solid Keeps
Shape
Keeps
Volume
No No
Liquid Takes
Shape of
Container
Keeps
Volume
No Yes
Gas Takes
Shape of
Container
Takes
Volume of
Container
Yes Yes
25. 25
Changes in Matter
Physical Changes are changes to matter
that do not result in a change the
fundamental components that make that
substance
State Changes – boiling, melting, condensing
Chemical Changes involve a change in the
fundamental components of the substance
Produce a new substance
Chemical reaction
Reactants Products
26. 26
Classify Each of the following as
Physical or Chemical Changes
Iron metal is melted.
Iron combines with oxygen to form
rust.
Sugar ferments to form ethyl alcohol.
27. 27
Classify Each of the following as
Physical or Chemical Changes
Iron is melted.
Physical change – describes a state change, but the
material is still iron
Iron combines with oxygen to form rust..
Chemical change – describes how iron and oxygen
react to make a new substance, rust
Sugar ferments to form ethyl alcohol.
Chemical change – describes how sugar forms a
new substance (ethyl alcohol)
28. 28
Elements and Compounds
Substances which can not be broken down
into simpler substances by chemical
reactions are called elements
Most substances are chemical combinations
of elements. These are called compounds.
Compounds are made of elements
Compounds can be broken down into elements
Properties of the compound not related to the
properties of the elements that compose it
Same chemical composition at all times
29. Most things in the universe are
made up of mixtures or a
compounds.
Compounds are chemically combined
Mixtures are physically combined
30. • Most elements react to form compounds.
• Example, H2O
• The proportions of elements in compounds are the
same irrespective of how the compound was formed.
• The composition of a pure compound is always the
same.
• If water is decomposed, then there will always be twice
as much hydrogen gas formed as oxygen gas.
• .
Compounds
30
،اتوار
14
،ّجالح ذو
1444
https://www.youtube.com/watch?v=r3ZiReLYGEM
31. • Heterogeneous mixtures are not uniform
throughout.
• Homogeneous mixtures are uniform
throughout.
• Homogeneous mixtures are called solutions.
Mixtures
31
،اتوار
14
،ّجالح ذو
1444
33. CHARACTERISTICS OF MIXTURE
It is an impure substance
No formula
They can be mixed in any ratio.
The properties of the mixture are the properties of its
constituents.
Constituents can be easily separated by physical methods
e.g. heating, drying, crystallization, distillation etc.
It is either homogenous or heterogeneous.
33
،اتوار
14
،ّجالح ذو
1444
https://www.youtube.com/watch?v=cL6I1O1YHH0
41. 41
Pure Substances vs. Mixtures
Pure Substances
All samples have the same physical and chemical properties
Constant Composition all samples have the same
composition
Homogeneous
Separate into components based on chemical properties
Mixtures
Different samples may show different properties
Variable composition
Homogeneous or Heterogeneous
Separate into components based on physical properties
All mixtures are made of pure substances
42. 42
Identity Each of the following as a
Pure Substance, Homogeneous
Mixture or Heterogeneous Mixture
Gasoline
A stream with gravel on the bottom
Copper metal
43. 43
Identity Each of the following as a
Pure Substance, Homogeneous
Mixture or Heterogeneous Mixture
Gasoline
a homogenous mixture
A stream with gravel on the bottom
a heterogeneous mixture
Copper metal
A pure substance (all elements are pure substances)
44. 44
Separation of Mixtures
Separate mixtures based on different
physical properties of the components
Physical change
Evaporation
Volatility
Chromatograph
y
Adherence to a Surface
Filtration
State of Matter
(solid/liquid/gas)
Distillation
Boiling Point
Technique
Different Physical Property
45. 45
Energy and Energy Changes
Capacity to do work
chemical, mechanical, thermal,
electrical, radiant, sound, nuclear
Energy may affect matter
e.g. raise its temperature, eventually
causing a state change
All physical changes and chemical
changes involve energy changes
46. 46
Heat
Heat: a flow of energy due to a temperature
difference
1. Exothermic = A process that results in the
evolution of heat.
Example: when a match is struck, it is an
exothermic process because energy is
produced as heat.
2. Endothermic = A process that absorbs
energy.
Example: melting ice to form liquid water is an
endothermic process.
47. 47
Units of Energy
One calorie is the amount of energy needed to
raise the temperature of one gram of water by
1°C
kcal = energy needed to raise the temperature of 1000
g of water 1°C
joule
4.184 J = 1 cal
In nutrition, calories are capitalized
1 Cal = 1 kcal
49. 49
Energy and the Temperature
of Matter
The amount the temperature of an object
increases depends on the amount of heat
added (Q).
If you double the added heat energy the
temperature will increase twice as much.
The amount the temperature of an object
increases depends on its mass
If you double the mass it will take twice as much
heat energy to raise the temperature the same
amount.
50. 50
Specific Heat Capacity
Specific Heat (s) is the amount of
energy required to raise the
temperature of one gram of a
substance by one Celsius degree
C
g
J
4.184
is
water
of
heat
specific
the
,
definition
By
Amount of Heat = Specific Heat x Mass x Temperature Change
Q = s x m x T
51. 51
Example – Calculate the amount of
heat energy (in joules) needed to
raise the temperature of 7.40 g of
water from 29.0°C to 46.0°C
Mass = 7.40 g
Temperature Change = 46.0°C – 29.0°C = 17.0°C
J
526
C
17.0
7.40g
C
g
J
4.184
Heat
Specific Heat of Water = 4.184
C
-
g
J
C
g
J
Q = s x m x T
52. 52
Example – A 1.6 g sample of metal that
appears to be gold requires 5.8 J to
raise the temperature from 23°C to
41°C. Is the metal pure gold?
C
g
J
0.20
C
18
x
g
1.6
J
5.8
s
C
18
C
23
-
C
41
T
T
m
Q
s
T
m
s
Q
Table 3.2 lists the specific heat of gold as 0.13
Therefore the metal cannot be pure gold.
56. Elements
Science has come
along way since
Aristotle’s theory of Air,
Water, Fire, and Earth.
Scientists have
identified 90 naturally
occurring elements,
and created about 28
others.
57. Elements
The elements,
alone or in
combinations,
make up our
bodies, our world,
our sun, and in
fact, the entire
universe.
60. Periodic Table
The periodic table organizes the elements in a
particular way. A great deal of information about an
element can be gathered from its position in the
period table.
For example, you can predict with reasonably good
accuracy the physical and chemical properties of
the element. You can also predict what other
elements a particular element will react with
chemically.
Understanding the organization and plan of the
periodic table will help you obtain basic information
about each of the 118 known elements.
61. Key to the Periodic Table
Elements are organized on
the table according to their
atomic number, usually
found near the top of the
square.
The atomic number
refers to how many
protons an atom of that
element has.
For instance, hydrogen
has 1 proton, so it’s
atomic number is 1.
The atomic number is
unique to that element.
No two elements have
the same atomic
number.
62. What’s in a square?
Different periodic
tables can include
various bits of
information, but
usually:
atomic number
symbol
atomic mass
number of valence
electrons
state of matter at room
temperature.
63. Atomic Number
This refers to how
many protons an
atom of that
element has.
No two elements,
have the same
number of protons.
Bohr Model of Hydrogen Atom
Wave Model
64. Atomic Mass
Atomic Mass refers
to the “weight” of
the atom.
It is derived at by
adding the number
of protons with the
number of
neutrons.
H
This is a helium atom. Its atomic
mass is 4 (protons plus
neutrons).
What is its atomic number?
65. Atomic Mass and Isotopes
While most atoms
have the same number
of protons and
neutrons, some don’t.
Some atoms have
more or less neutrons
than protons. These
are called isotopes.
An atomic mass
number with a decimal
is the total of the
number of protons plus
the average number of
neutrons.
66. Atomic Mass Unit (AMU)
The unit of
measurement for
an atom is an AMU.
It stands for atomic
mass unit.
One AMU is equal
to the mass of one
proton.
67. Atomic Mass Unit (AMU)
There are
6 X 1023 or
600,000,000,000,000,
000,000,000 amus in
one gram.
(Remember that
electrons are 2000
times smaller than
one amu).
68. Symbols
All elements have
their own unique
symbol.
It can consist of a
single capital letter,
or a capital letter
and one or two
lower case letters.
C Carbon
Cu
Copper
70. Valence Electrons
The number of valence
electrons an atom has
may also appear in a
square.
Valence electrons are the
electrons in the outer
energy level of an atom.
These are the electrons
that are transferred or
shared when atoms bond
together.
71.
72. Properties of Metals
Metals are good conductors
of heat and electricity.
Metals are shiny.
Metals are ductile (can be
stretched into thin wires).
Metals are malleable (can
be pounded into thin
sheets).
A chemical property of
metal is its reaction with
water which results in
corrosion.
73. Properties of Non-Metals
Non-metals are poor
conductors of heat and
electricity.
Non-metals are not
ductile or malleable.
Solid non-metals are
brittle and break easily.
They are dull.
Many non-metals are
gases.
Sulfur
74. Properties of Metalloids
Metalloids (metal-like)
have properties of both
metals and non-metals.
They are solids that can
be shiny or dull.
They conduct heat and
electricity better than non-
metals but not as well as
metals.
They are ductile and
malleable.
Silicon
75.
76.
77. Families Periods
Columns of elements are
called groups or families.
Elements in each family
have similar but not
identical properties.
For example, lithium (Li),
sodium (Na), potassium
(K), and other members of
family IA are all soft,
white, shiny metals.
All elements in a family
have the same number of
valence electrons.
Each horizontal row of
elements is called a
period.
The elements in a period
are not alike in properties.
In fact, the properties
change greatly across
even given row.
The first element in a
period is always an
extremely active solid. The
last element in a period, is
always an inactive gas.
78.
79.
80.
81.
82.
83.
84.
85.
86.
87.
88.
89.
90. Hydrogen
The hydrogen square sits atop Family
AI, but it is not a member of that family.
Hydrogen is in a class of its own.
It’s a gas at room temperature.
It has one proton and one electron in its
one and only energy level.
Hydrogen only needs 2 electrons to fill
up its valence shell.
91. Alkali Metals
The alkali family is found in
the first column of the
periodic table.
Atoms of the alkali metals
have a single electron in
their outermost level, in
other words, 1 valence
electron.
They are shiny, have the
consistency of clay, and are
easily cut with a knife.
92. Alkali Metals
They are the most
reactive metals.
They react violently
with water.
Alkali metals are
never found as free
elements in nature.
They are always
bonded with
another element.
93. What does it mean to be
reactive?
We will be describing elements according to their
reactivity.
Elements that are reactive bond easily with other
elements to make compounds.
Some elements are only found in nature bonded
with other elements.
What makes an element reactive?
An incomplete valence electron level.
All atoms (except hydrogen) want to have 8 electrons in
their very outermost energy level (This is called the rule of
octet.)
Atoms bond until this level is complete. Atoms with few
valence electrons lose them during bonding. Atoms with 6,
7, or 8 valence electrons gain electrons during bonding.
97. Alkaline Earth Metals
They are never found uncombined in nature.
They have two valence electrons.
Alkaline earth metals include magnesium
and calcium, among others.
98. Transition Metals
Transition Elements
include those elements
in the B families.
These are the metals
you are probably most
familiar: copper, tin,
zinc, iron, nickel, gold,
and silver.
They are good
conductors of heat and
electricity.
99. Transition Metals
The compounds of transition metals are usually
brightly colored and are often used to color paints.
Transition elements have 1 or 2 valence electrons,
which they lose when they form bonds with other
atoms. Some transition elements can lose electrons
in their next-to-outermost level.
100. Transition Elements
Transition elements have properties
similar to one another and to other
metals, but their properties do not fit in
with those of any other family.
Many transition metals combine
chemically with oxygen to form
compounds called oxides.
101. Boron Family
The Boron Family is
named after the first
element in the family.
Atoms in this family have 3
valence electrons.
This family includes a
metalloid (boron), and the
rest are metals.
This family includes the
most abundant metal in the
earth’s crust (aluminum).
102. Carbon Family
Atoms of this family have
4 valence electrons.
This family includes a
non-metal (carbon),
metalloids, and metals.
The element carbon is
called the “basis of life.”
There is an entire branch
of chemistry devoted to
carbon compounds called
organic chemistry.
103. Nitrogen Family
The nitrogen family is named
after the element that makes
up 78% of our atmosphere.
This family includes non-
metals, metalloids, and
metals.
Atoms in the nitrogen family
have 5 valence electrons.
They tend to share electrons
when they bond.
Other elements in this family
are phosphorus, arsenic,
antimony, and bismuth.
104. Oxygen Family
Atoms of this family have 6
valence electrons.
Most elements in this family
share electrons when
forming compounds.
Oxygen is the most
abundant element in the
earth’s crust. It is extremely
active and combines with
almost all elements.
105. Halogen Family
The elements in this
family are fluorine,
chlorine, bromine,
iodine, and astatine.
Halogens have 7
valence electrons, which
explains why they are
the most active non-
metals. They are never
found free in nature.
Halogen atoms only need
to gain 1 electron to fill their
outermost energy level.
They react with alkali
metals to form salts.
106. Noble Gases
Noble Gases are colorless gases that are extremely un-
reactive.
One important property of the noble gases is their inactivity.
They are inactive because their outermost energy level is full.
Because they do not readily combine with other elements to
form compounds, the noble gases are called inert.
The family of noble gases includes helium, neon, argon,
krypton, xenon, and radon.
All the noble gases are found in small amounts in the earth's
atmosphere.
107. Rare Earth Elements
The thirty rare earth
elements are composed
of the lanthanide and
actinide series.
One element of the
lanthanide series and
most of the elements in
the actinide series are
called trans-uranium,
which means synthetic or
man-made.
108. Mendeleev
In 1869, Dmitri Ivanovitch
Mendeléev created the first accepted
version of the periodic table.
He grouped elements according to
their atomic mass, and as he did, he
found that the families had similar
chemical properties.
Blank spaces were left open to add
the new elements he predicted
would occur.
109. Matter
All matter is composed of atoms and groups
of atoms bonded together, called molecules.
Substances that are made from one type of
atom only are called pure substances.
Substances that are made from more than one
type of atom bonded together are called
compounds.
Compounds that are combined physically, but
not chemically, are called mixtures.
110. Elements, Compounds,
Mixtures
Sodium is an element.
Chlorine is an
element.
When sodium and
chlorine bond they
make the compound
sodium chloride,
commonly known as
table salt.
Compounds have different properties
than the elements that make them up.
Table salt has different properties than
sodium, an explosive metal, and chlorine,
a poisonous gas.
111. Elements, Compounds,
Mixtures
Hydrogen is an element.
Oxygen is an element.
When hydrogen and
oxygen bond they make
the compound water.
When salt and water are
combined, a mixture is
created. Compounds in
mixtures retain their
individual properties.
The ocean is
a mixture.
112. Elements, compounds, and
mixtures
Mixtures can be separated by physical
means.
Compounds can only be separated by
chemical means.
Elements are pure substances. When the
subatomic particles of an element are
separated from its atom, it no longer retains
the properties of that element.
