Periodic Table of Elements

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Periodic Table of Elements
MEET THE
ELEMENTS
Pages 124-167
Ch.4.1, 4.2, 4.3, 4.4 and 5.1
Dmitri Mendeleev
•He recognized patterns in
the element’s approximate
atomic masses and their
ability to bond with other
elements.
Periodic Table
•Based on atomic masses and
their ability to bond with
other elements, Mendeleev
constructed the first
periodic Table.
The Atom
•Nucleus: The core of the atom
that contains two different
subatomic particles.
The Atom cont…
•Protons: Have a positive charge.
•The number of protons equals the
number of electrons.
The Atom cont…
•Neutrons: Have no
Charge.
The Atom cont…
•Electrons Negative
charge.
•.
Atomic Numbers, Symbols and
• Atomic
Mass
number is
the smaller
number and
the number
of protons
in the
nucleus.
47
Ag
Element
Symbol
Element
Name
Silver
107.868
Atomic mass is the average mass
of all the known isotopes.
How to calculate # of neutrons
• Mass number - Atomic number = # of neutrons
This element is
Nitrogen. Its
mass # is 14. So
mass # of 14,
minus atomic #
Count the number of 7, equals 7
of protons. What neutrons.
element is it?
How to Calculate Number of
Electrons
• The number of electrons equal the
number of protons.
7
electrons
7
protons
How many neutrons does Mn
(Manganese) have?
30
1.
2.
3.
4.
25
55
7
30
0%
0%
0%
2
3
0%
0
1
4
How many Neutrons does K
(Potassium) have?
1.
2.
3.
4.
19
20
39
11
0%
0 of 30
1
0%
0%
2
3
0%
4
10
30
How many Protons does Hg
Have?
1. 80
2. 200
3. 120
0%
0%
0%
0
1
2
3
30
How many Electrons does Hg
Have?
1. 80
2. 200
3. 120
0%
0%
0%
0
1
2
3
Isotopes
•When atoms of the same
element have a different
number of neutrons
Valence Electrons
•The electrons on
the outermost ring
or energy level
that can be shared
or transferred
with other atoms
to make
compounds.
Valence Electrons and
Bonding (ch. 5.1 pgs. 176-182)
The number of valence electrons
in an atom of an element
determines many properties of
that element, including the ways
in which the atom can bond with
other atoms.
When an atom has a different # of
neutrons it’s called a…
1.
2.
3.
4.
Ion
Isotope
Proton
Element
0%
0%
0%
2
3
0%
0 of 30
1
4
30
What subatomic particle influences
an elements ability to bond?
1.
2.
3.
4.
Protons
Neutrons
Valence Electrons
Nucleus
0%
0%
0%
2
3
0%
0
1
4
Groups –Families
Periods- elements in a
elements period are not alike,
in a
but gradually change as
group
you move from left to
have veryright.
similar characteristics
i.e. bonding, reactivity,
valence electrons
METALS
•Almost 75% of
all elements are
classified as
metals.
Properties of Metals
•Conductors: Metals are
good at conducting
electricity.
• Malleable: Ability to
bend or pound into
shapes.
Properties of
Metals
• Ductile: Pull or stretch
into wire.
• Many are shiny, hard and
magnetic.
• High melting point
Which of the following would be the
best conductor of electricity?
1. Carbon (atomic number 6)
2. Strontium (atomic number 38)
3. Tellurium (atomic number 52)
0
of
30
0%
1
0%
2
What is a characteristic of metals?
1.
2.
3.
4.
Gas
Stable
Good conductor
Brittle
30
0
0%
0
1
0%
0%
2
3
0%
4
Metals are malleable, which
means…
1. Pound or mold
into shape
2. Brittle
3. Stretch into wire
0
of
30
0%
1
0%
2
0%
3
What do all elements in a
group/family have in common?
1. Same # of Valence
electrons
2. Same # of protons
3. Same # of
rings/shells/energy
levels
0
of
30
0%
1
0%
2
0%
3
ALKALI METALS-Group 1
•So reactive that they
are never found
isolated in nature,
only combined with
other elements.
ALKALI METALS-Group 1
Characteristics Properties:
• Soft
• Shiny
• One valance: electron makes them
very reactive.
The Sodium in the class demo reacted
so violently because it has…
30
1. 3 protons
2. 1 neutron
3. 2 valence
electrons
4. 1 valence electron
0%
0%
0%
2
3
0%
0
1
4
What family is Hydrogen in?
1.
2.
3.
4.
Alkali
Alkaline Earth
Halogens
No Family
0%
0%
0%
2
3
0%
0 of 30
1
4
Alkaline Earth Metals
•Group 2 metals.
•Very reactive, not as
reactive as alkali metals due
to having one more valence
electron.
•Ca: important for bones.
Metalloids
Have some properties of both
metals and nonmetals.
They are located on the
zigzag line between the
metals and the nonmetals.
Physical Properties:
•Can be good at conducting electricity, therefore
some are used as computer chips such as Si
and Ge.
•Non metals lack properties of
metals.
•They are on the right side of the
periodic table.
Fe
Non-metals
O
Fe2O3 = Iron Oxide = Rust
•Non metals usually react with metals to make
compounds.
•In general, metals give up electrons to nonmetals.
Properties of Metals cont…
•Reactivity: Ability to react
and combine with other
elements. Some are more
reactive than others.
Sodium (Na) and potassium
(K) are some of the most
reactive metals.
Which of the following
elements is most likely to react?
1. Chlorine
2. Helium
3. Iron
0
of
30
0%
1
0%
2
0%
3
What are the group 17 (7A)
elements called?
30
1.
2.
3.
4.
Alkaline Earth
Rare Earth
Halogen
Transition Metals
0
0%
1
0%
2
0%
3
0%
4
30
What is the Group/Family name
of the elements in BLUE?
1.
2.
3.
4.
5.
6.
7.
Alkali
Alkaline Earth
Transition
Metalloids
Halogen
Noble Gas
Rare Earth
14%
14%
14%
14%
14%
14%
14%
0
1
2
3
4
5
6
7
What is the Group/Family name
of the elements in RED?
30
1.
2.
3.
4.
5.
6.
7.
Alkali
Alkaline Earth
Transition
Metalloids
Halogen
Noble Gas
Rare Earth
14%
14%
14%
14%
14%
14%
14%
0
1
2
3
4
5
6
7
What is the Group/Family name
of the elements in GREEN?
30
1.
2.
3.
4.
5.
6.
7.
Alkali
Alkaline Earth
Transition
Metalloids
Halogen
Noble Gas
Rare Earth
14%
14%
14%
14%
14%
14%
14%
0
1
2
3
4
5
6
7
Predicting Reactions
• Elements become more stable as they gain
more valence electrons.
• As a result, atoms will gain, lose or share
electrons to form compounds so that they
have 8 valence electrons or a full shell.
• This is called the Octet Rule. However
there are many exceptions, but this is an
easy way to predict common reactions.
Atoms are “happy” when they have either
only 2 valence electrons (He) or 8
electrons.
Families of Non-metals
• The Halogen family is
group 17 (7A). Each
element has 7 valence
electrons, therefore it
commonly takes one
electron away from
group one metals to
make compounds.
Families of Non-metals
•The Noble Gases are
group 18 (8A). They
have 8 valence
electrons, therefore
they are very stable
and non-reactive.
Hydrogen
•Not a part
of group 1.
•Generally
found as H2
•It doesn’t fit into any other family
because it is so different from all other
elements.
Group 17 (7A) has 7 valence
electrons and are called the
30
1. Alkali metals
2. Alkaline Earth
Metals
3. Halogens
4. Noble Gases
0%
0%
0%
2
3
0%
0
1
4
Group 18 (8A) has 8 valence
electrons and are called
30
1. Alkali metals
2. Alkaline Earth
Metals
3. Halogens
4. Noble Gases
0%
0%
0%
2
3
0%
0
1
4
30
What element would Na (Sodium)
bond with?
1.
2.
3.
4.
Br
K
W
Al
0%
0%
0%
2
3
0%
0
1
4
What element would Mg
(Magnesium) bond with?
30
1.
2.
3.
4.
Au
Na
Se
Kr
0%
0%
0%
2
3
0%
0
1
4
How many Hydrogen atoms would
bond to one N (Nitrogen)?
1.
2.
3.
4.
6
2
8
3
0%
1
0%
0%
2
3
0%
4
Matter
•Anything that has
mass and takes up
space
States of matter
The four states of
matter are solids,
liquids, gasses and
plasma.
Elements
•Can’t be broken down
into another substance.
Atom
•The smallest particle of
an element. Basic unit of
all matter
Element vs. Compound
•An ELEMENT is a pure
substance made up of only
one type of atom.
•They may exist as atoms like
the Noble Gases e.g. helium
He or as molecules e.g.
hydrogen H2 or sulfur S2
Compound
•Chemical Combination of 2 or
more DIFFERENT elements.
•EX: H20water
CO2Carbon Dioxide
C12022H11 Sugar
C6H12O6 Glucose
A type of
Molecule
chocolate
Formula
•Ratio of atoms of each
element in a compound.
Theobromine, C7H8O4N2
or Chocolate
Law of Conservation of Matter
•Matter is neither created nor
destroyed during a chemical
change.
•It recombines to make a new type
of chemical.
Changes in Matter
•Physical Change: When
the state of matter
changes.
Physical Change
• whipping egg whites (air is forced into the fluid, but no
new substance is produced)
• magnetizing a compass needle (there is realignment of
groups ("domains") of iron atoms, but no real change
within the iron atoms themselves).
• boiling water (water molecules are forced away from
each other when the liquid changes to vapor, but the
molecules are still H2O.)
• dissolving sugar in water (sugar molecules are dispersed
within the water, but the individual sugar molecules are
unchanged.)
• dicing potatoes (cutting usually separates molecules
without changing them.)
Changes in Matter cont…
•Chemical Change: When a
substance(s) combines or
decompose into a new
substance.
Examples of a chemical change
iron rusting (iron oxide forms)
gasoline burning (water vapor and carbon
dioxide form)
eggs cooking (fluid protein molecules uncoil and
crosslink to form a network)
bread rising (yeast converts carbohydrates into
carbon dioxide gas)
milk souring (sour-tasting lactic acid is
produced)
suntanning (vitamin D and melanin is produced)
5
1. Chemical change
only
2. Physical change
only
3. Both physical and
chemical change
0%
0%
0%
0
1
2
3
5
1. Chemical change
only
2. Physical change
only
3. Both physical and
chemical change
0%
0%
0%
0
1
2
3
5
He, O2, N2, and Ne are all:
1. Atoms
2. Elements
3. Compounds
0%
0%
0%
0
1
2
3
5
1. Atoms
2. Elements
3. Compounds/molecules
0%
0%
0%
0
1
2
3
5
H2, H2O, N2, and NaCl are all:
1.
2.
3.
4.
Atoms
Elements
Compounds
Molecules
0%
0%
0%
0
1
2
3
5
1. H, O, Na, Cl and C
2. H2O, NaCl and CO2
0
0%
1
0%
2
30
1. Chemical
change
2. Destroying
matter
3. Physical change
33%
1
0
33%
2
33%
3
30
1. A change in state
2. A different
substance with
different
properties
3. No new
substance
33%
33%
33%
0
1
2
3
30
1. Chemical
change
2. Physical change
3. Both a chemical
and a physical
change
33%
33%
33%
0
1
2
3
Characteristic Properties
•Regardless of state of
matter, a substance has a
unique characteristic
property.
Chapter 3 sections 1
and 3
•Definite Shape and
Definite Volume.
•Molecules are packed
closely together and
slightly vibrate.
• Very large molecules made of a chain of
smaller molecules
• Polymers form when chemical bonds link large
numbers of monomers in a repeating pattern.
• The properties of synthetic polymers
make them ideal starting materials for
many common objects.
•Takes the shape of the
container that it’s in.
•Atoms and/or molecules are
loosely packed together.
•A mixture where
particles can be seen
and easily separated.
•Examples: Milk, salad
dressing and muddy
water
The resistance of a liquid
to flow.
The higher the viscosity,
the slower it will flow.
Usually amorphic solids.
•Have no definite shape
and no definite volume.
•Very compressible.
•Particles are not touching,
therefore the
Intermolecular forces are
broken.
•Movement is random and
independent of each other.
What are Galaxies?
•They are large groups of stars
•There are billions of stars in a galaxy
Types of Galaxies
There are 3 main types of galaxies
• Spiral: it has a nucleus
• Irregular: it has not specific
shape
• Elliptical: it is a bright ball
and is generally older
Our Galaxy
•It contains over
100 billion stars
•It is about 100,000
light-years in
diameter and
10,000 light-years
thick
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