# THE PERIODIC TABLE

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Nov 1, 2013 (4 years and 7 months ago)

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THE PERIODIC TABLE

Chapter 7

THE PERIODIC TABLE

Lesson 1

Using the Periodic Table

Lesson 2

Metals

Lesson 3

Nonmetals and Metalloids

LESSON 1: USING THE PERIODIC TABLE

Key Concepts

How are elements arranged on the periodic table?

What can you learn about elements from the periodic table?

LESSON 1: USING THE PERIODIC TABLE

What is the periodic table?

The
peri
odic table
is a chart of the elements
arranged into rows and columns according to their
physical and chemical properties.

It can be used to determine the relationships
among the elements.

LESSON 1: USING THE PERIODIC TABLE

Developing a periodic table

When Russian chemist
Dimitri

Mendeleev was
working on classifying the elements, he placed his
list of elements into a table and arranged them in
rows of increasing atomic mass.

Elements with similar properties were grouped in
the same column.

LESSON 1: USING THE PERIODIC TABLE

Mendeleev noticed that melting point is one
property that shows a repeating pattern.

LESSON 1: USING THE PERIODIC TABLE

Developing a periodic table (cont.)

Boiling point and reactivity also follow a periodic
pattern.

Mendeleev believed that the atomic masses of
certain elements must be invalid because the
elements appeared in the wrong place on the
periodic table.

He placed elements whose properties resembled
each other’s closer together in the table.

LESSON 1: USING THE PERIODIC TABLE

When Moseley listed the elements according to
atomic number, columns contained elements with
similar properties, such as copper, silver, and gold.

LESSON 1: USING THE PERIODIC TABLE

Today’s periodic table

You can identify many of the properties of an
element from its placement on the periodic table.

period

Science Use

the completion of a
cycle; a row on the periodic table

Common Use

a point used to mark
the end of a sentence; a time frame

LESSON 1: USING THE PERIODIC TABLE

The table is organized into columns, rows, and
blocks, which are based on certain patterns of
properties.

LESSON 1: USING THE PERIODIC TABLE

Today’s periodic table (cont.)

The element key shows an element’s chemical
symbol, atomic number, and atomic mass.

The key also contains a symbol that shows the
state of matter at room temperature.

LESSON 1: USING THE PERIODIC TABLE

Today’s periodic table (cont.)

A

group

is a column on the periodic table.

Elements in the same group have similar chemical
properties and react with other elements in similar
ways.

LESSON 1: USING THE PERIODIC TABLE

Today’s periodic table (cont.)

The rows on the periodic table are called
periods
.

The atomic number of each element increases by
one as you read from left to right across each
period.

LESSON 1: USING THE PERIODIC TABLE

Today’s periodic table

Metals are on the left side and in the middle of the
periodic table.

With the exception of hydrogen, nonmetals are
located on the right side of the periodic table.

Between the metals and the nonmetals on the
periodic table are the metalloids.

LESSON 1: USING THE PERIODIC TABLE

How scientists use the periodic table

Even today, new elements are created in
laboratories, named, and added to the present
-
day
periodic table.

LESSON 1: USING THE PERIODIC TABLE

How scientists use the periodic table (cont.)

Scientists can use the periodic table to predict the
properties of new elements they create.

The periodic table contains more than 100
elements, each with its unique properties that
differ from the properties of other elements.

LESSON 1: USING THE PERIODIC TABLE

Summary

On the periodic table, elements are arranged according to
increasing atomic numbers and similar properties.

A column of the periodic table is called a group. Elements in
the same group have similar properties.

A row of the periodic table is called a period. Properties of
elements repeat in the same pattern from left to right
across each period.

LESSON 2: METALS

Key Concepts

What elements are metals?

What are the properties of metals?

LESSON 2: METALS

What is a metal?

More than three
-
quarters of the elements on the
periodic table are metals.

With the exception of hydrogen, all of the elements
in groups 1
-
12
on the periodic table are metals.

Some of the elements in groups 13
-
15 are metals.

To be a metal, an element must have certain
properties.

LESSON 2: METALS

What is a metal? (cont.)

A
metal

is an element that is generally shiny. It is
easily pulled into wires or hammered into thin
sheets. A metal is a good conductor of electricity
and thermal energy.

Luster

describes the ability of a metal to reflect
light.

Ductility

is the ability to be pulled into thin wires
.

LESSON 2: METALS

What is a metal? (cont.)

Malleability

is the ability of a substance to be
hammered or rolled into sheets.

Gold is so malleable that it can be hammered into
thin sheets.

In general the density, strength, boiling point, and
melting point of a metal are greater than those of
other elements.

LESSON 2: METALS

Group 1: Alkali Metals

The elements in group 1 are called
alkali metals
.

The alkali metals include lithium, sodium,
potassium, rubidium, cesium, and francium.

Alkali metals react quickly with other elements,
such as oxygen and in nature, occur only in
compounds.

Alkali metals react violently

with water. They are also soft

enough to be cut with a knife.

LESSON 2: METALS

Group 2: Alkaline Earth Metals

The elements in group 2 on the periodic table are
called
alkaline earth metals
.

The alkaline earth metals are beryllium, magnesium,

Pure alkaline earth

metals do not occur

combine with other

elements and form

compounds.

LESSON 2: METALS

Groups 3
-
12: Transition Elements

The elements in groups 3
-
12 are called
transition
elements
.

T
ransition elements are in a block at the center and
two rows at the bottom of the periodic table.

Many colorful materials contain small amounts of
transition elements.

LESSON 2: METALS

Groups 3
-
12: Transition Elements (cont.)

All transition elements are metals with higher melting
points, greater strength, and higher densities than the
alkali metals and the alkaline earth metals.

Because of their high densities, strength, and
resistance to corrosion, transition elements make good
building materials.

Two rows of transition elements

the lanthanide and
actinide series

were removed from the main part of
the table so that periods 6 and 7 were not longer than
the other periods.

LESSON 2: METALS

Patterns in properties of metals

Metallic properties include luster, malleability, and
electrical conductivity.

LESSON 2: METALS

Summary

Properties of metals include conductivity, luster,
malleability, and ductility.

Alkali metals and alkaline earth metals react easily
with other elements. These metals make up groups
1 and 2 on the periodic table.

Transition elements make up groups 3
-
12 and the
lanthanide and actinide series on the periodic
table.

LESSON 3: METALS AND METALLOIDS

Key Concepts

Where are nonmetals and metalloids on the
periodic table?

What are the properties of nonmetals and
metalloids?

LESSON 3: METALS AND METALLOIDS

The elements of life

More than 96 percent of
the mass of the human
body comes from four
nonmetals

oxygen,
carbon, hydrogen, and
nitrogen.

LESSON 3: METALS AND METALLOIDS

The elements of life (cont.)

Nonmetals

are elements that have no metallic
properties.

The four elements that make up most of the human
body, along with phosphorus and sulfur, are the six
elements in proteins, fats, nucleic acids, and other
large molecules in your body and in all other living
things.

LESSON 3: METALS AND METALLOIDS

How are nonmetals different from metals?

Nonmetals have properties that are different from
those of metals.

Many nonmetals are gases at room temperature
and those that are solid at room temperature have
a dull surface, which means they have no luster.

Because nonmetals are poor conductors of
electricity and thermal energy, they are good
insulators.

LESSON 3: METALS AND METALLOIDS

Phosphorus and carbon are dull, brittle solids that
do not conduct thermal energy or electricity.

LESSON 3: METALS AND METALLOIDS

How are nonmetals different from metals?
(cont.)

An element in group 17 of the periodic table is
galled a
halogen
.

The term
halogen
refers to an element that can
react with a metal and form a salt.

LESSON 3: METALS AND METALLOIDS

How are nonmetals different from metals? (cont.)

Halogens react readily with other elements and form
compounds.

Halogens can only occur naturally in compounds.

In general, halogens are less reactive as you move
down the group.

The elements in group 18 are known as the
noble
gases
.

LESSON 3: METALS AND METALLOIDS

How are nonmetals different from metals? (cont.)

Unlike the halogens, the only way elements in this
group react with other elements is under special
conditions in a laboratory.

Of all the elements, hydrogen has the smallest atomic
mass and is the most common element in the universe.

Hydrogen is most often classified as a nonmetal
because it has many properties like those of
nonmetals.

However, hydrogen also has some properties similar to
those of the group 1 alkali metals.

Under conditions on Earth, hydrogen usually behaves
as a nonmetal.

LESSON 3: METALS AND METALLOIDS

Metalloids

Between the metals and the nonmetals on the
periodic table are elements known as metalloids.

LESSON 3: METALS AND METALLOIDS

Metalloids (cont.)

A
metalloid

is an element that has physical and
chemical properties of both metals and nonmetals.

The elements boron, silicon, germanium, arsenic,
antimony, tellurium, polonium, and astatine are
metalloids.

Silicon is the most abundant metalloid in the
universe.

LESSON 3: METALS AND METALLOIDS

Metalloids (cont.)

A property of metalloids is the ability to act as a
semiconductor.

A
semiconductor

conducts electricity at high
temperatures, but not at low temperatures.

Silicon is used in making semiconductor devices for
computers and other electronic products.

LESSON 3: METALS AND METALLOIDS

Metals, nonmetals, and metalloids

An element’s position on the periodic table tells you

Understanding the properties of elements can help
you decide which element to use in a given
situation.

LESSON 3: METALS AND METALLOIDS

Summary

A nonmetal is an element that has no metallic
properties. Solid nonmetals are dull and brittle and
do not conduct thermal energy or electricity.

Halogens and noble gases are nonmetals. These
elements are found in group 17 and group 18 of
the periodic table.

Metalloids have some metallic properties and some
nonmetallic properties. The most important use of
metalloids is as semiconductors.

CHAPTER WRAP
-
UP

Lesson 1: Using the Periodic Table

Elements are organized on the periodic table by
increasing atomic number and similar properties.

Elements in the same group, or column, of the
periodic table have similar properties.

Elements’ properties change across a period, which
is a row of the periodic table.

Each element key on the periodic table

provides the name, symbol, atomic number, and
atomic mass for an element.

CHAPTER WRAP
-
UP

Lesson 2: Metals

Metals are located on the left and middle parts of
the periodic table.

Metals are elements that have ductility,
malleability, luster, and conductivity.

The alkali metals are in group 1 of the periodic
table, and the alkaline earth metals are in group 2.

Transition elements are metals in groups 3
-
12 of
the periodic table, as well as the lanthanide and
actinide series.

CHAPTER WRAP
-
UP

Lesson 3: Nonmetals

and Metalloids

Nonmetals are on the

right
side of the periodic table, and metalloids are
located between metals and nonmetals.

Nonmetals are elements that have no metallic
properties. Solid nonmetals are dull in appearance,
brittle, and do not conduct electricity. Metalloids are
elements that have properties of both metals and
nonmetals.

Some metalloids are semiconductors.

Elements in group 17 are called halogens, and
elements in group 18 are noble gases.