Transcript periodic table - Montville.net

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15.1 The Periodic Table of the
Elements
Periodic Table Timeline
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Lavoiser (1770-1789) Composed the first
list of 33 elements. Distinguished metals
from nonmetals.
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Meyer (1869) Compiled a periodic table with
elements arranged by atomic weight.
Elements with similar properties arranged in
columns.
Mendeleev (1869) Created a periodic table
with elements arranged by atomic weight.
Elements with similar properties arranged in
columns.
Moseley (1914) Determined atomic numbers
of each element.
15.1 Physical properties
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Remember phase changes are physical
changes.
15.1 Chemical properties
 Any
change that transforms one
substance into a different substance is
called a chemical change.
15.1 The Periodic Table
 The
periodic table organizes the elements
according to how they combine with other
elements (chemical properties).
 The periodic table is organized in order of
increasing atomic number.
15.1 The Periodic Table
Each horizontal row is
called a period.
 Each vertical column
is called a group or
family.
Elements
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Metals
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Nonmetals
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Metalloids
Metals
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Almost 75% of elements are metals
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Most are solids at room temperature
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exception-Hg(mercury)
Alkali Metals(Group 1)
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Very reactive
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Shiny and light weight
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Only found combined with other
elements
One electron in their outer shell
Alkaline Earth Metals (Group 2)
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Not as reactive as the alkali metals
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Have 2 electrons in the outer shell
Transition Metals
(Groups 3 to 12)
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Less reactive than alkali or alkaline earth
metals
Properties vary widely examples: Hg –
liquid, titanium is not very reactive but
iron is.
Electrons in the 2 outer most shells can
bond with other elements
Lanthanides/Inner Transition
Metals
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Follow the element lanthanum
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Shiny and reactive
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Used to make different types of steel
Actinides
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Follow the metal actinium
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Radioactive
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Unstable
Groups with Metalloids
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Groups 13 to 16 shift from metals to
nonmetals with some metalloids in
between
They have properties of both metals and
nonmetals
Groups 13 to 16
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Boron Group - 3 electrons in the outer shell
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Carbon Group -4 electrons in the outer shell
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Nitrogen Group - 5 electrons in the outer shell
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Oxygen Group- 6 electrons in the outer shell
Carbon and carbon-like elements
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Almost all the molecules that
make up plants and animals
are constructed around
carbon.
The chemistry of carbon is
so important it has its own
name, organic chemistry.
Nitrogen, oxygen and phosphorus
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Oxygen and nitrogen are
crucial to living animals and
plants.
For example, proteins and
DNA both contain nitrogen.
Phosphorus is a key
ingredient of DNA, the
molecule responsible for
carrying the genetic code in
all living creatures.
15.2 Nitrogen, oxygen and
phosphorus
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Phosphorus is a key
ingredient of DNA, the
molecule responsible for
carrying the genetic code
in all living creatures.
When phosphorus atoms
absorb light, they store
energy, then release it in a
greenish glow.
Halogens(Group 17)
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Very reactive nonmetal
Seven electrons in the outer shell
Often bond with metals
Fluorine is the most reactive
Never found uncombined in nature
Form halides-a halogen combined with
another element to form a compound
Noble Gases (Group 18)
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Have full outer shell with 8 electrons,
except for Helium which has 2.
Rarely combine with other elements
Non-reactive (inert)
Colorless and Odorless
Gases at room temperature
HYDROGEN
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Stands apart
Only 1 electron in the outer energy level
Very reactive
Other properties: colorless, odorless gas
at room temperature; low density; reacts
explosively with oxygen.
15.2 Periodic properties of elements
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Periodicity means properties repeat each
period (row) of the periodic table.
Energy Levels And The Periodic
Table
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The periods (rows) of the Periodic Table
correspond to the energy levels in the
Bohr model of the atom. The first energy
level can accept up to two electrons
therefore Period 1 is the first energy level.
Period 2 is the 2nd energy level
Period 3 is the third energy level and so
on.
Energy Levels And The Periodic
Table
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The outermost electrons in an atom are
the ones that interact with other atoms.
They are also the electrons that are in the
highest energy level.
Electrons in the completely filled inner
energy levels do not participate in forming
chemical bonds.