Chapter 4 Elements and the Periodic Table

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Chapter 4 Elements and the Periodic Table
Table of Contents
Chapter Preview
4.1 Introduction to Atoms
4.2 Organizing the Elements
4.3 Metals
4.4 Nonmetals, Inert Gases, and Semimetals
4.5 Radioactive Elements
Chapter 4 Elements and the Periodic Table
Chapter Preview Questions
1. Groups of two or more atoms held together by chemical
bonds are
a. elements.
b. molecules.
c. particles.
d. electrons.
Chapter 4 Elements and the Periodic Table
Chapter Preview Questions
1. Groups of two or more atoms held together by chemical
bonds are
a. elements.
b. molecules.
c. particles.
d. electrons.
Chapter 4 Elements and the Periodic Table
Chapter Preview Questions
2. When elements are chemically combined in a set ratio,
they form
a. molecules.
b. matter.
c. elements.
d. compounds.
Chapter 4 Elements and the Periodic Table
Chapter Preview Questions
2. When elements are chemically combined in a set ratio,
they form
a. molecules.
b. matter.
c. elements.
d. compounds.
Chapter 4 Elements and the Periodic Table
Chapter Preview Questions
3. Which of the following is an example of an element?
a. copper
b. rust
c. concrete
d. water
Chapter 4 Elements and the Periodic Table
Chapter Preview Questions
3. Which of the following is an example of an element?
a. copper
b. rust
c. concrete
d. water
Chapter 4 Elements and the Periodic Table
Chapter Preview Questions
4. Two compounds with different properties are
a. C and O.
b. H and O.
c. CO and CO2.
d. Cl and Ar.
Chapter 4 Elements and the Periodic Table
Chapter Preview Questions
4. Two compounds with different properties are
a. C and O.
b. H and O.
c. CO and CO2.
d. Cl and Ar.
Chapter 4 Elements and the Periodic Table
How is the periodic table organized?
Imagine you have a piece of
aluminum foil, and you cut it
in half. If each of these pieces is
cut in half a second, third, and
fourth time, the pieces become
smaller but are still aluminum.
How small must a piece be so
that at the next cut it will no
longer be aluminum?
Chapter 4 Elements and the Periodic Table
Greek Word Origins
Greek Origin
alpha
Meaning
Key Words
First letter of the Greek
alphabet
Alpha particle
Chapter 4 Elements and the Periodic Table
Greek Word Origins
Greek Origin
atomos
Meaning
Key Words
Cannot be cut; indivisible
Atom, atomic number,
atomic mass
Chapter 4 Elements and the Periodic Table
Greek Word Origins
Greek Origin
beta
Meaning
Key Words
Second letter of the Greek
alphabet
Beta particle
Chapter 4 Elements and the Periodic Table
Greek Word Origins
Greek Origin
di
Meaning
Key Words
Two, double
Diatomic molecule
Chapter 4 Elements and the Periodic Table
Greek Word Origins
Greek Origin
gamma
Meaning
Key Words
Third letter of the Greek
alphabet
Gamma radiation
Chapter 4 Elements and the Periodic Table
Greek Word Origins
Greek Origin
hals
Meaning
Key Words
Salt, relating to salt
Halogen
Chapter 4 Elements and the Periodic Table
Apply It!
Review the Greek origins and meanings in the chart. What is the
meaning of the prefix di- in diatomic? Predict the meaning of
diatomic molecule. Revise your definition as needed.
Sample: Since diatomos means “two atoms,” di- probably means “two.”
Chapter 4 Elements and the Periodic Table
End of Chapter
Preview
Chapter 4 Elements and the Periodic Table
Section 1:
Introduction to Atoms
How did atomic theory develop and change?
What is the modern model of the atom?
Chapter 4 Elements and the Periodic Table
Atomic Theory and Models
Dalton thought that atoms were like smooth, hard balls that
could not be broken into smaller pieces.
Chapter 4 Elements and the Periodic Table
Atomic Theory and Models
Thomson suggested that atoms had negatively charged
electrons embedded in a positive sphere.
Chapter 4 Elements and the Periodic Table
Rutherford’s Gold Foil Experiment
Rutherford was surprised that a few particles were deflected
strongly. This led him to propose an atomic model with a
positively charged nucleus.
Chapter 4 Elements and the Periodic Table
Later Atomic Models
Through the first part of the twentieth century, atomic models
continued to change.
Chapter 4 Elements and the Periodic Table
Modern Model of an Atom
This model of a carbon atom consists of positively charged
protons and neutral neutrons in a nucleus that is surrounded
by a cloud of negatively charged electrons.
Chapter 4 Elements and the Periodic Table
Particles in an Atom
An atom is composed of positively charged protons, neutral
neutrons, and negatively charged electrons. Protons and
neutrons are about equal in mass. An electron has about
1/2,000 the mass of a proton or neutron.
Chapter 4 Elements and the Periodic Table
Isotopes
Atoms of all isotopes of carbon contain six protons and six
electrons, but they differ in their number of neutrons. Carbon12 is the most common isotope.
Chapter 4 Elements and the Periodic Table
More on Atomic Structure
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about atomic structure.
Chapter 4 Elements and the Periodic Table
End of Section:
Introduction to Atoms
Chapter 4 Elements and the Periodic Table
Section 2:
Organizing the
Elements
How did Mendeleev discover the pattern that led to the
periodic table?
How are the elements organized in the modern periodictable?
Chapter 4 Elements and the Periodic Table
The Periodic Table
Elements are organized into rows and
columns based on their atomic number.
Chapter 4 Elements and the Periodic Table
The Periodic Table
Elements are organized into
rows and columns based on
their atomic number.
Chapter 4 Elements and the Periodic Table
The Periodic Table
Elements are organized into
rows and columns based on
their atomic number.
Chapter 4 Elements and the Periodic Table
Periodic Table Activity
Click the Active Art button to open a browser window and
access Active Art about the periodic table.
Chapter 4 Elements and the Periodic Table
Finding Data on Elements
Each square in the periodic table lists four pieces of
information: an element’s atomic number, chemical symbol,
name, and atomic mass.
Chapter 4 Elements and the Periodic Table
End of Section:
Organizing the
Elements
Chapter 4 Elements and the Periodic Table
Section 3:
Metals
What are the physical properties of metals?
How does the reactivity of metals change across the
periodic table?
How are synthetic elements produced?
Chapter 4 Elements and the Periodic Table
Metals in the Periodic Table
The metals in Group 1, from lithium to francium, are
called the alkali metals. Alkali metals react with atoms
of other elements by losing one electron.
Chapter 4 Elements and the Periodic Table
Metals in the Periodic Table
Group 2 of the periodic table contains the alkaline
earth metals. These elements are not as reactive as
the metals in Group 1, but they are more reactive
than most other metals.
Chapter 4 Elements and the Periodic Table
Melting Points in a Group of Elements
The properties of elements
within a single group in the
periodic table often vary in a
certain pattern. The following
graph shows the melting points
of Group 1 elements (alkali
metals) from lithium to francium.
Chapter 4 Elements and the Periodic Table
Melting Points in a Group of Elements
Reading Graphs:
As you look at Group 1 from
lithium to francium, describe
how the melting points of the
alkali metals change.
Melting points decrease from
lithium to francium.
Chapter 4 Elements and the Periodic Table
Melting Points in a Group of Elements
Predicting:
If element number 119 were
synthesized, it would fall
below francium in Group 1 of
the periodic table. Predict the
approximate melting point of
new element 119.
New element 119 should
have a melting point of
approximately 25ºC or lower.
Chapter 4 Elements and the Periodic Table
Melting Points in a Group of Elements
Interpreting Data:
Which of the alkali metals are
liquids at 35ºC?
Cesium, francium
Chapter 4 Elements and the Periodic Table
Metals in the Periodic Table
The transition metals are less reactive than the metals in
Groups 1 and 2.
Chapter 4 Elements and the Periodic Table
Metals in the Periodic Table
Only some of the elements in Groups 13 through 15 of the
periodic table are metals.
Chapter 4 Elements and the Periodic Table
Metals in the Periodic Table
Lanthanides are usually found together in nature, always
combined with other elements.
Chapter 4 Elements and the Periodic Table
Metals in the Periodic Table
The elements below the lanthanides are called actinides.
Many of these elements are so unstable that they last for
only a fraction of a second after they are made.
Chapter 4 Elements and the Periodic Table
Links on Metals
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Chapter 4 Elements and the Periodic Table
End of Section:
Metals
Chapter 4 Elements and the Periodic Table
Section 4:
Nonmetals, Inert
Gases, and
Semimetals
What are the properties of nonmetals and inert gases?
How are semimetals useful?
Chapter 4 Elements and the Periodic Table
Properties of Nonmetals
When nonmetals and metals react, electrons move from the
metal atoms to the nonmetal atoms.
Chapter 4 Elements and the Periodic Table
Families of Nonmetals
Each element in the carbon family has atoms that
can gain, lose, or share four electrons when reacting
with other elements.
Chapter 4 Elements and the Periodic Table
Families of Nonmetals
Group 15, the nitrogen family, contains two
nonmetals: nitrogen and phosphorus. These nonmetals usually gain or share three electrons when
reacting with other elements.
Chapter 4 Elements and the Periodic Table
Families of Nonmetals
Group 16, the oxygen family, contains three
nonmetals: oxygen, sulfur, and selenium. These
elements usually gain or share two electrons when
reacting with other elements.
Chapter 4 Elements and the Periodic Table
Families of Nonmetals
The Group 17 elements, the halogens, are very
reactive. Atoms of these elements easily form
compounds by sharing or gaining one electron when
reacting with atoms of other elements.
Chapter 4 Elements and the Periodic Table
Families of Nonmetals
The elements in Group 18 are the inert gases. They
do not ordinarily form compounds because atoms of
inert gases do not usually gain, lose, or share
electrons.
Chapter 4 Elements and the Periodic Table
Families of Nonmetals
Because the chemical properties of hydrogen differ very
much from those of the other elements, it really cannot be
grouped into a family.
Chapter 4 Elements and the Periodic Table
Semimetals
The most useful property of the semimetals is their varying
ability to conduct electric current.
Chapter 4 Elements and the Periodic Table
Links on Nonmetals
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Chapter 4 Elements and the Periodic Table
End of Section:
Nonmetals, Inert Gases,
and Semimetals
Chapter 4 Elements and the Periodic Table
Section 5:
Radioactive Elements
How was radioactivity discovered?
What types of particles and energy can radioactive decay
produce?
In what ways are radioactive isotopes useful?
Chapter 4 Elements and the Periodic Table
Types of Radioactive Decay
During alpha decay, a nucleus loses an alpha particle, which
consists of two protons and two neutrons.
Chapter 4 Elements and the Periodic Table
Types of Radioactive Decay
During beta decay, a neutron inside an unstable nucleus
changes into a negatively charged beta particle and a proton.
Chapter 4 Elements and the Periodic Table
Types of Radioactive Decay
Gamma radiation has no charge and does not cause a
change in either the atomic mass or the atomic number.
Chapter 4 Elements and the Periodic Table
Types of Radioactive Decay
The three types of nuclear radiation were named based on
how easily each one could be blocked. Alpha, beta, and
gamma are the first three letters of the Greek alphabet.
Chapter 4 Elements and the Periodic Table
Using Radioactive Isotopes
Tracers are radioactive isotopes that can be followed through
the steps of a chemical reaction or industrial process.
Chapter 4 Elements and the Periodic Table
Radioactive Tracers Activity
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access Active Art about radioactive tracers.
Chapter 4 Elements and the Periodic Table
Radiation
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Chapter 4 Elements and the Periodic Table
End of Section:
Radioactive Elements
Chapter 4 Elements and the Periodic Table
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