The number of protons and
neutrons in the nucleus of an atom
An abreviation of the
element name
The number of protons of
protons found in the nucleus of
an atom
Or
The number of electrons
surrounding the nucleus of an
atom
How can find the number of Protons,
Electrons and Neutrons in a element using the
Periodic Table
# of protons =
Atomic number
# of Electrons =
Atomic number
# of Neutrons = Atomic
Weight -- Atomic
number
ELEMENTS: The elements, alone or in
combinations , make upor bodies, our
world, or sun, and in fact, the entire
universe
The most abundant element
in the earth´s crust in oxigen
The elements of the periodic table con be divided into three main
categories Metals, Non-Metals , and Metalloids
Elements in the periodic table are also grouped
into families, wich are the colums. Elements in
families have similar properties
The elements are also categorized into periods, or horizontal rows
Elements in periods do not have similar properties
While most atoms have the same number of Protons and Neutrons, some don´t
Some atoms have more or less Neutrons and
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
Common elements and symbols
METALS
Metals are good conductors of heat
and electricity
Metals are
shiny
Metals are malleabe (Can be
pounded into thin sheets)
A chemical property of metal is its reaction with water wich results in
corrosion
NON-METALS
Non-Metals are poor conductoors of heat and electricity
Non-Metals are not ductile or malleable
Solid Non-Metals are bittle and break easily
They are dull
Many Non-Metals are gases
METALLOIDS
Metallodis (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 nometals but not as well as metals
They are ductile and malleable
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
Colums of elements are
called groups or families
PERIODS
Each horizontal row of elements is called a
period
The elements is a period are not alike in
properties
The first element in a period is always an extremely active solid. The last element in a period, is always an inactive gas
In fact, the properties change greatly acrosseven given
row
FAMILIES IN THE PERIOD TABLE OF
ELEMENTS
Periodic Table of the Elements
Hydrogen
The hydrogen square
sits atop Family AI,
but it is not a member
of that fsmily.
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
ALKALI METALS
The alkali family is
found in the first
colum 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 conssistency
of clay and are easly cut with a knife
They are the most reactive
metal
They ract violenty whith
water
Alkali metals are never found as free elements in nature. They are always bonded with another
element
ALKALINE EARTH METALS
They have two valence Electrons
They are never found uncobined in nature
Alkaline earth metals include
magnesium and calcium, among others.
What does it mean to be reactive?
We will be describing elements acording 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 valance Electron
level
All atoms (Expept hydrogen) want to have 8 electrons in their
very outermost energy level (This is called the rule of octent
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
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
TRANSITION METALS
The compouds of transition metals are usually
brightly colored and are often used to color
paints
Transition elements have 1 or 2 valence electrons, wich they lose when
they form bonds with other atoms. Some transition elements can lose
electrons in their next- to- outermost level
TRANSITION ELEMENTS
Transition elements haver 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
BORON FAMILY
The Boron family is named after the first element in the
family
This family includes the most abundant metal in the earth´s crust
(aluminium)
This family includes a metalloid (boron), and the rest are
metals
Atoms in this famili
have 3 valence
Electrons
CARBON FAMILY
Atoms is the 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 brant of chemistry devoted to carbon compound called organic chemistry
NITROGEN
FAMILY
The nitrogen family is named after the element that make 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 the family are phosphorus,
arsenic, antimony, and bismuth
OXYGEN FAMILY
Atoms of this family have 6 valence Electrons
Oxigen is the most abundantelement in the earth´s crust. It is extremely active and combines with almost all elements
Most elements in this family share Electrons when forming compounds
HALOGEN FAMILY
The elements in this family are fluorine, chloroine, bromine, iodine, and astatine
Alogen atoms only need to gain 1 Electron to fill their outermost energy level
Halogens have 7 valence Electrons, wich explains why they are the most active Non-Metals. They are
never found free in nature
They react with alkali metals to form salts
RARE EARTH ELEMENTS
One element of the lanthanide series and most of the elements in the actinide series
are called trans-uranium, wich means syntethic or man-made
The thirty rare earth elements are composed of the lathanide and actanide series
NOBLE GASES
Noble Gases are colorlessgases that are extremely un-reactive
One important property of the Noble Gases is their inactivity. Thy are inactivy because their outermost
energy level is full
Thefamily of Noble Gases includes helium, neon, argon, krypton, xenon, and radon
Noble gases are called
inert
All the Noble Gases are found in small amounts in the earth´s atmosphere