Upload
others
View
8
Download
0
Embed Size (px)
Citation preview
ORGANIZING THE ELEMENTS
3/8/16 Objective:
Students will be able to describe how
elements belonging to a group or period are
interrelated on the periodic table.
© Copyright Pearson Prentice Hall
Slide
2 of 28
6.1 Organizing the Elements
In a self-service store, the products are grouped according to similar characteristics. With a logical classification system, finding and comparing products is easy. You will learn how elements are arranged in the periodic table and what that arrangement reveals about the elements.
Slide
3 of 28
© Copyright Pearson Prentice Hall
Organizing the Elements > Searching For an Organizing Principle
Elements are organized using their
properties. Chlorine, bromine, and iodine
have very similar chemical properties.
They are all in group 7A.
6.1
© Copyright Pearson Prentice Hall
Organizing the Elements >
Slide
4 of 28
Mendeleev’s Periodic Table
Mendeleev’s Periodic Table
How did Mendeleev organize his
periodic table?
6.1
Slide
5 of 28
© Copyright Pearson Prentice Hall
Organizing the Elements > Mendeleev’s Periodic Table
Mendeleev arranged the elements in his
periodic table in order of increasing
atomic mass.
This first table was used to predict the
properties of undiscovered elements. The
presence of Gallium was predicted based on
this table
Problem- some elements didn’t line up with
other elements that had similar properties
Example: I and Te were out of place
6.1
Slide
6 of 28
© Copyright Pearson Prentice Hall
Organizing the Elements > Mendeleev’s Periodic Table
An Early Version of Mendeleev’s Periodic Table
6.1
© Copyright Pearson Prentice Hall
Organizing the Elements >
Slide
7 of 28
The Periodic Law
The Periodic Law
How is the modern periodic table
organized?
Moseley developed the organization
used in the modern periodic table.
6.1
Slide
8 of 28
© Copyright Pearson Prentice Hall
Organizing the Elements > The Periodic Law
In the modern periodic table elements are
arranged in order of increasing atomic
number.
Atomic number = # of protons
Protons are in the nucleus
Nucleus has a positive charge
6.1
Slide
9 of 28
© Copyright Pearson Prentice Hall
Organizing the Elements > The Periodic Law
The periodic law: When elements are arranged in order of increasing atomic number, there is a periodic repetition of their physical and chemical properties.
• The properties of the elements within a period change as you move across a period from left to right.
• The pattern of properties within a period repeats as you move from one period to the next.
6.1
Slide
10 of 28
© Copyright Pearson Prentice Hall
Organizing the Elements > Groups and Periods
Remember that:
a group is a vertical column
a period is a horizontal row
Groups have similar properties because they have the same number of valence electrons
For groups 1A-8A the number of valence electrons matches the group number (with the exception of He)
For groups 1B-8B the number of valence electrons is 1 or 2 and must be found using electron configurations.
© Copyright Pearson Prentice Hall
Slide
11 of 28
Organizing the Elements > Metals, Nonmetals, and Metalloids
Three classes of elements are metals,
nonmetals, and metalloids.
Across a period, the properties of elements
become less metallic and more nonmetallic.
Use the following slides to help you color in
the 3 classes of elements using colored
pencils.
6.1
© Copyright Pearson Prentice Hall
Slide
12 of 28
Organizing the Elements > Metals, Nonmetals, and Metalloids
Metals, Metalloids, and Nonmetals in the Periodic Table
6.1
© Copyright Pearson Prentice Hall
Slide
13 of 28
Organizing the Elements > Metals, Nonmetals, and Metalloids
Metals, Metalloids, and Nonmetals in the Periodic Table
6.1
© Copyright Pearson Prentice Hall
Slide
14 of 28
Organizing the Elements > Metals, Nonmetals, and Metalloids
Metals, Metalloids, and Nonmetals in the Periodic Table
6.1
© Copyright Pearson Prentice Hall
Slide
15 of 28
Organizing the Elements > Metals, Nonmetals, and Metalloids
Metals, Metalloids, and Nonmetals in the Periodic Table
6.1
Slide
16 of 28
© Copyright Pearson Prentice Hall
Organizing the Elements > Metals, Nonmetals, and Metalloids
Metals
Metals are good conductors of heat and electric
current.
• 80% of elements are metals.
• Metals have a high luster, are ductile, and are
malleable.
6.1
Slide
17 of 28
© Copyright Pearson Prentice Hall
Organizing the Elements > Metals, Nonmetals, and Metalloids
Uses of Iron, Copper, and Aluminum
6.1
Slide
18 of 28
© Copyright Pearson Prentice Hall
Organizing the Elements > Metals, Nonmetals, and Metalloids
Uses of Iron, Copper, and Aluminum
6.1
Slide
19 of 28
© Copyright Pearson Prentice Hall
Organizing the Elements > Metals, Nonmetals, and Metalloids
Uses of Iron, Copper, and Aluminum
6.1
Slide
20 of 28
© Copyright Pearson Prentice Hall
Organizing the Elements > Metals, Nonmetals, and Metalloids
Nonmetals
In general, nonmetals are poor conductors of heat and electric current.
• Most nonmetals are gases at room temperature.
• A few nonmetals are solids, such as sulfur and phosphorus. These solids are brittle.
• One nonmetal, bromine, is a dark-red liquid.
6.1
Slide
21 of 28
© Copyright Pearson Prentice Hall
Organizing the Elements > Metals, Nonmetals, and Metalloids
Metalloids
A metalloid generally has some properties of
metals and some properties of nonmetals.
The behavior of a metalloid can be controlled by
changing conditions.
A metalloid may be brittle, lustrous, and a good
conductor, like silicon.
6.1
Slide
22 of 28
© Copyright Pearson Prentice Hall
Organizing the Elements > Metals, Nonmetals, and Metalloids
If a small amount of boron is mixed with silicon,
the mixture is a good conductor of electric
current. Silicon can be cut into wafers, and used
to make computer chips.
6.1
6.1 SECTION QUIZ
1. The modern periodic table has elements
arranged in order of
colors.
melting and boiling points.
increasing atomic mass.
increasing atomic number.
6.1 SECTION QUIZ
2. Mendeleev arranged the elements in his
periodic table in order of increasing
atomic number.
atomic mass.
number of electrons.
number of protons
6.1 SECTION QUIZ
3. Which one of the following is NOT a general
property of metals?
poor conductor of heat and electricity
malleability
having a high luster
ductility
CLASSWORK!
Reading Assignment: Sec 6.1
Written Assignment: p. 166, #1-7
DO NOW ACTIVITY
This will be collected and count as part of your
classwork/participation grade for today.
HOMEWORK CHECK!
Page 166, #1-7 1. Chemists used the properties of elements to sort them into
groups.
2. Mendeleev used atomic mass to organize his periodic table.
3. The elements are arranged in order of increasing atomic number on the modern periodic table.
4. The three broad classes of elements are: metals, metalloids, and nonmetals.
5. a. metal b. metalloid c. nonmetal d. metal
6. B
7. Lithium, Potassium, Rubidium, Cesium, or Francium all have similar properties to Sodium.
HOW ARE ELEMENTS FURTHER CLASSIFIED ON
THE PERIODIC TABLE?
Just like the Atomic Number of an elements
can be similar to your SSN, and the Electron
Configuration of an element is similar to your
fingerprints, the periodic table can tell us
information about each element, just like a
driver’s license or ID card.
CLASSIFYING ELEMENTS SECTION 6.2
3/8/16
Students will understand the correlation
between valence electrons, electron
configuration, and element organization of
the periodic table.
FOUR MAIN CATEGORIES OF ELEMENTS
Transition Metals
Inner Transition Metals
Noble Gases
Representative Elements
USE THIS TO HELP OUTLINE THE CATEGORIES ON YOUR PERIODIC TABLE
FOUR MAIN CATEGORIES OF ELEMENTS
Transition Metals: Group B elements that are
usually displayed in the main body of the
periodic table
metallic elements
outermost s & d sublevels contain electrons
Contain either 1 or 2 valence electrons
Examples of elements: Tungsten (W), Vanadium (V),
Gold (Au), Nickel (Ni)
FOUR MAIN CATEGORIES OF ELEMENTS
Inner transition metals: the elements that
appear below the main body of the periodic
table.
metallic elements
outermost s & nearby f sublevel contain electrons
Lanthanides and actinides
Actinides are all radioactive
Examples of elements: Cerium (Ce), Europium (Eu),
Plutonium (Pu), Californium (Cf)
FOUR MAIN CATEGORIES OF ELEMENTS
Noble Gases- the elements in Group 8A of the periodic table.
s & p sublevels filled
8 valence electrons: ns2 ….np6
Except He, which has 2 valence : 1s2
Inert (not reactive) because of full outer shell of electrons (8 valence electrons)
Examples of elements: Xenon (Xe), Helium (He), Krypton (Kr)
FOUR MAIN CATEGORIES OF ELEMENTS
Representative Elements: also called main group elements and are located in Groups 1A-7A
s & p partly filled
Includes alkali metals, alkaline earth metals, and halogens
Large variation in properties
Examples of elements: Sodium (Na), Calcium (Ca), Nitrogen (N), Tin (Sn)
REPRESENTATIVE ELEMENTS
6.2
REPRESENTATIVE ELEMENTS
6.2
REPRESENTATIVE ELEMENTS
6.2
REPRESENTATIVE ELEMENTS
6.2
ALKALI, ALKALINE EARTH, HALOGENS Alkali Metals- group 1A
very reactive 1 valence electron: ns1
Loses 1 electron to be stable forming +1 charge
Alkaline Earth Metals– group 2A Less reactive than alkali
2 valence electrons: ns2
Loses 2 electrons to be stable, forming +2 charge
Halogens- group 7A Very reactive
Nonmetals
7 valence electrons: ns2….np5
Gains 1 electrons to be stable, forming -1 charge
REVIEW- ELECTRON CONFIGURATIONS FROM
THE PERIODIC TABLE
ELECTRON CONFIGURATIONS IN GROUPS
The Noble Gases
The electron configurations for the first four noble gases
in Group 8A are listed below.
6.2
ELECTRON CONFIGURATIONS IN GROUPS
Alkali Metals
In atoms of the Group 1A elements below, there is only
one electron in the highest occupied energy level.
6.2
ELECTRON CONFIGURATIONS IN GROUPS
Representative Elements
In atoms of the Group 4A elements below, there are four
electrons in the highest occupied energy level.
6.2
CLASSWORK!
Reading Assignment: Section 6.2
Written Assignment: p. 173, #12-15, 17
HOMEWORK!!
Complete the worksheet on comparing and
contrasting different aspects of the periodic
table.