C HAPTER
6 TE Periodic Table
Chapter Outline
6.1 CHAPTER6: PERIODICTABLE
6.1. Chapter 6: Periodic Table www.ck12.org
6.1 Chapter 6: Periodic Table
Chapter Overview
Mendeleev developed the first periodic table of the elements, which he based on atomic mass. The modern periodic table is based on atomic number. Elements can be grouped in three major classes: metals, nonmetals, and metalloids.
They differ in their number of valence electrons, which explains many of their properties. Group 1 of the periodic table consists of hydrogen and the alkali metals, group 2 consists of the alkaline Earth metals, groups 3–12 contain transition metals, groups 13–16 each contain at least one metalloid as well as metals and/or nonmetals, and group 18 consists of noble gases. Reactivity of elements generally decreases from group 1 through group 18.
Online Resources
See the following Web sites for appropriate laboratory activities:
The following URL has links to several periodic table labs.
• http://www.nclark.net/PeriodicTable
The lab at the URL below is a high-school lab on the properties of metals and nonmetals, but it has adaptations for younger students.
• http://www.discoveryeducation.com/teachers/free-lesson-plans/pursuit-of-the-properties-of-metals-and-nonmeta ls.cfm
Try this online video lab when you teach classes of elements in Lesson 6.2.
• http://schoolwaxtv.com/learn-lab-files-neutralisation
With this lab, students can explore trends in reactivity in the periodic table: http://www.berenato.net/Labs/Periodi cTrendslab .
These Web sites may also be helpful:
These URLs have interactive periodic tables that provide in-depth information about each element.
• http://periodic.lanl.gov/index.shtml
• http://www.rsc.org/periodic-table
These Web sites offer a plethora of middle school resources about the periodic table.
• http://www.science-class.net/Chemistry/periodic_table.htm
• http://www.middleschoolscience.com/chemistry.htm
Pacing the Lessons
T
ABLE6.1:
Pacing the LessonsLesson Class Period(s) (60 min)
6.1 How Elements Are Organized 1.5
6.2 Classes of Elements 2.0
6.3 Groups of Elements 2.0
6.2. Lesson 6.1 How Elements Are Organized www.ck12.org
6.2 Lesson 6.1 How Elements Are Organized
Key Concept
Mendeleev developed the first periodic table of the elements in 1869. He organized the elements by increasing atomic mass. The modern periodic table is based on atomic number. Elements in each period go from metals on the left to metalloids and then to nonmetals on the right. Within groups of the periodic table, elements have similar properties.
Standards
• SCI.CA.8.PS.3.a, f; SCI.CA.8.PS.7.a, b
• MCR.6-8.SCI.8.4
• NSES.5-8.A.2.1; NSES.5-8.B.1.3
• AAAS.6-8.4.D.2, 8; AAAS.6-8.11.B.5; AAAS.6-8.11.C.4; AAAS.6-8.12.D.2
Lesson Objectives
• Describe Mendeleev’s periodic table of the elements.
• Give an overview of the modern periodic table of the elements.
Lesson Vocabulary
• group: column of the periodic table, which contains elements with similar properties
• period: row of the periodic table that contains elements ranging from metals on the left to metalloids and then to nonmetals on the right
• periodic table: table of elements arranged by increasing atomic number (modern periodic table) or by increasing atomic mass (Mendeleev’s periodic table)
Teaching Strategies
Introducing the Lesson
Introduce the periodic table with a deck of cards. Lay out the cards by suit and number where students can see them.
Create a 4-column by 13-row grid by placing the cards in each suit in a separate column, starting with the ace in the first row and ending with the king in the last row. Discuss how the cards in the rows and columns form regular
patterns (e.g., all the cards in row 1 are aces, all the cards in column 1 are spades). Tell students they will learn in this lesson how elements are also arranged in rows and columns that form regular patterns.
Using Visuals
Have students look at the modern periodic table in the FlexBook® lesson. Point out how atomic number (number of protons) increases across each period and down each row. Make sure students understand the placement of the lanthanides and actinides. Then, review the information provided by the table and have students apply it by answering the following questions:
Question: Bromine is a nonmetal with the chemical symbol Br. How many protons does it have?
Answer: Bromine’s atomic number is 35, so it has 35 protons.
Question: Nickel has the chemical symbol Ni and is in period 4. In which class of elements is nickel?
Answer: Nickel is a metal.
Question: Find hydrogen, represented by the chemical symbol H, in the upper left corner of the periodic table.
What can you infer about hydrogen from the table?
Answer: Hydrogen is a nonmetal with an atomic number of 1, which means that it has 1 proton.
Activity
Using resources from the following URL, play “Element Bingo” with the class. It will help students learn the chemical names of the elements, which is very helpful for using the periodic table.
• http://education.jlab.org/beamsactivity/6thgrade/elementbingo/index.html Differentiated Instruction
Help students distinguish between periods and rows of the periodic table. Work with them to make a compare/contrast table for period and group like the sampleTable6.2.
T
ABLE6.2:
Periodic TablePeriod or Group? What Is It? How Many Are There? How Does Atomic Num- ber Change?
Period row of the table 7 increases by 1 from left to
right
Group column of the table 18 increases by different
amounts from top to bottom
Enrichment
Challenge a small group of creative students to invent a board game using the periodic table as the game board. For example, players might roll dice to determine which element to land on with their game piece, and the winner might be the first player to land on a certain number of elements in each class. Encourage other students to play the game to help familiarize them with the periodic table.
6.2. Lesson 6.1 How Elements Are Organized www.ck12.org Science Inquiry
Have groups of students solve the “Alien Periodic Challenge” describe at the URL below (under “Labs”). You can find links to all the materials you need at the Web site.
• http://www.nclark.net/PeriodicTable
Common Misconceptions
Avoid the following misconceptions about the periodic table. The History Connection that follows is one way to help avoid them.
• The periodic table in its present form is the way the elements have always been organized.
• There is only one way to organize the elements.
History Connection
Give students a more detailed history of the periodic table. The URLs below are good sources of information.
Students will better appreciate how many different scientists have contributed to the development of this fundamental tool of chemistry.
• http://en.wikipedia.org/wiki/History_of_the_periodic_table
• http://www.wou.edu/las/physci/ch412/perhist.htm
• http://www.bpc.edu/mathscience/chemistry/history_of_the_periodic_table.html
Reinforce and Review
Lesson Worksheets
Copy and distribute the lesson worksheets in theCK-12 Physical Science for Middle School Workbook. Ask students to complete the worksheets alone or in pairs to reinforce lesson content.
Lesson Review Questions
Have students answer the Review Questions listed at the end of the lesson in the FlexBook® student edition.
Lesson Quiz
Check students’ mastery of the lesson with Lesson 6.1 Quiz inCK-12 Physical Science for Middle School Quizzes and Tests.
Points to Consider
Elements are classified as metals, metalloids, or nonmetals.
• Do you know some examples of metals?
• How do you think metals might differ from the other two classes of elements?
6.3. Lesson 6.2 Classes of Elements www.ck12.org
6.3 Lesson 6.2 Classes of Elements
Key Concept
Metals are the largest class of elements. They are good conductors of electricity and heat, and many are shiny, ductile, and malleable. Most metals are solids at room temperature. Nonmetals are the second largest class of elements. They do not conduct electricity, are poor conductors of heat, and the majority are gases. Metalloids are elements that have properties of both metals and nonmetals, and all are solids at room temperature. Atoms of elements in different classes vary in their number of valence electrons, and this explains many of their properties.
Standards
• SCI.CA.8.PS.3.a, f; SCI.CA.8.PS.7.a, c
• MCR.6-8.SCI.8.5, 9
• NSES.5-8.A.1.5; NSES.5-8.B.1.1, 2
• AAAS.6-8.4.D.8, 9, 15, 16
Lesson Objectives
• Identify properties of metals.
• List properties of nonmetals.
• Describe metalloids.
• Relate valence electrons to reactivity of elements by class.
Lesson Vocabulary
• metal: class of elements that are good conductors of electricity
• metalloid: class of elements that have some properties of metals and some properties of nonmetals
• nonmetal: class of elements that do not conduct electricity
• valence electron: electron in the outer energy level of an atom that is potentially involved in chemical reactions
Teaching Strategies
Introducing the Lesson
Focus students’ attention on elements in the periodic table with one of the “Periodic Table Teaser” PowerPoint presentations at the following URL.
• http://sciencespot.net/Pages/startersphysci.html
Activity
Have students complete the interactive activity at the URL below. They will be presented with the main classes of elements and their properties, followed by quiz questions to check their understanding.
• http://www.wisc-online.com/Objects/ViewObject.aspx?ID=GCH6004
Discussion
Discuss with the class the general differences between metals and nonmetals. The URL below provides a good summary of their differences. Include a discussion of the chemical property of electronegativity and relate it to the number of valence electrons in metals and nonmetals. This information will be important when they learn about chemical bonds in subsequent chapters of the FlexBook® resource.
• http://hyperphysics.phy-astr.gsu.edu/hbase/pertab/metal.html
Differentiated Instruction
Discuss with the class the general differences between metals and nonmetals. The URL below provides a good summary of their differences. Include a discussion of the chemical property of electronegativity and relate it to the number of valence electrons in metals and nonmetals. This information will be important when they learn about chemical bonds in subsequent chapters of the FlexBook® resource.
• http://hyperphysics.phy-astr.gsu.edu/hbase/pertab/metal.html
Enrichment
Ask a few students to create a display of some common objects that consist of metals (e.g., aluminum can, copper wire) and other objects that consist of nonmetals (e.g., charcoal, match). Then have them use the objects to demonstrate some of the properties of each class of elements.
Science Inquiry
Have groups of students do Science Inquiry Activity 2, “Elemental Classification,” at the URL below. They will compare some of the chemical properties of metals and nonmetals.
• http://dev.nsta.org/ssc/pdf/v4-0961s.pdf
6.3. Lesson 6.2 Classes of Elements www.ck12.org Health Connection
Describe the role of metals in good health. You can learn which metals are vital to human health and the roles they play at these URLs:
• http://www.livescience.com/18247-metals-human-body-health-nigms.html
• http://www.eurometaux.eu/MetalsToday/MetalsFAQs/Metalsessentialforhumanhealth.aspx
Reinforce and Review
Lesson Worksheets
Copy and distribute the lesson worksheets in theCK-12 Physical Science for Middle School Workbook. Ask students to complete the worksheets alone or in pairs to reinforce lesson content.
Lesson Review Questions
Have students answer the Review Questions listed at the end of the lesson in the FlexBook® student edition.
Lesson Quiz
Check students’ mastery of the lesson with Lesson 6.2 Quiz inCK-12 Physical Science for Middle School Quizzes and Tests.
Points to Consider
The number of valence electrons increases from left to right across each period of the periodic table. By the end of the period, the outer energy level is full. Moving on to the next period of the table, electrons are added to the next higher energy level. This happens in each row of the periodic table.
• How do you think the number of valence electrons compares in elements within the same column (group) of the periodic table?
• How might this be reflected in the properties of elements within a group?
6.4 Lesson 6.3 Groups of Elements
Key Concept
Group 1 of the periodic table consists of hydrogen and the alkali metals. All of them are very reactive. Group 2 consists of the alkaline Earth metals. They are very reactive but less so than Group 1 elements. Groups 3–12 contain transition metals, which are less reactive than metals in groups 1 and 2. Groups 13–16 each contain at least one metalloid as well as metals and/or nonmetals, and they vary in reactivity and other properties. Group 17 contains halogens, which are highly reactive nonmetals. Group 18 consists of noble gases, which are unreactive.
Standards
• SCI.CA.8. PS.3.a, f; SCI.CA.8.PS.7.a, c
• MCR.6-8.SCI.8.5, 9, 10
• NSES.5-8.A.1.5; NSES.5-8.B.1.1, 2
• AAAS.6-8.4.D.8, 9, 10, 15, 16, 17
Lesson Objectives
• Identify hydrogen and alkali metals.
• Describe alkaline Earth metals.
• List properties of transition metals.
• Identify groups containing metalloids.
• Give properties of halogens.
• Describe noble gases.
Lesson Vocabulary
• alkali metal:metal in group 1 of the periodic table that has one valence electron and is highly reactive
• alkaline Earth metal:metal in group 2 of the periodic table that has two valence electrons and is very reactive but less so than an alkali metal
• halogen:nonmetal in group 17 of the periodic table that has seven valence electrons and is highly reactive
• noble gas: nonmetal in group 18 of the periodic table that has eight valence electrons (or two in the case of helium) and is unreactive
• transition metal: metal in groups 3 to 12 of the periodic table that is hard and shiny and less reactive than metals in groups 1 and 2
6.4. Lesson 6.3 Groups of Elements www.ck12.org
Teaching Strategies
Introducing the Lesson
At the start of class, demonstrate the reactivity of alkali metals with the excellent video at the URL below. Alter- natively (or in addition), you can do a live demonstration of one or more alkali metals reacting with water. The vigorous reaction will be sure to get students’ attention and pique their interest in alkali metals. Explain that a vigorous reaction with water is a characteristic property of all metals in group 1 of the periodic table. Tell students they will learn in this lesson the properties of all the groups in the periodic table.
• http://www.open.edu/openlearn/science-maths-technology/science/chemistry/alkali-metals
Building Science Skills
Ask students to predict the properties of a few specific elements in different groups, based on their general knowledge of each group. They can check their predictions by finding the properties of the specific elements in this interactive periodic table:
• http://www.rsc.org/periodic-table
Activity
Have students try to match each element to the class or group to which it belongs by doing the activity at the following URL. They can check their answers at the Web site.
• http://www.sciencegeek.net/Chemistry/taters/Unit2ElementClasses.htm
Differentiated Instruction
Assign each student one of the vocabulary terms in the lesson so all the terms are covered. Then ask students to make a Frayer model for their term. They should draw a large box, divide it into four parts labeled “Definition,”
“Drawing,” “Example,” and “Non-example,” and then fill in the box for their term.
Enrichment
Challenge a few students to role-play elements in different groups by acting out their properties. Ask the rest of the students to guess which groups they are role-playing.
Science Inquiry
Describe a few “mystery elements” from different groups, and challenge students to identify in which group each element belongs. You can find detailed information about specific elements at this URL:
• http://periodic.lanl.gov/index.shtml
Common Misconceptions
The activity at the URL below will reveal and correct misconceptions about the periodic table. It uses concept mapping to explore and revise students’ ideas. It is also a good way to review Chapter 6 concepts.
• http://media.rsc.org/Misconceptions/Miscon%20periodic%20table.pdf
Reinforce and Review
Lesson Worksheets
Copy and distribute the lesson worksheets in theCK-12 Physical Science for Middle School Workbook. Ask students to complete the worksheets alone or in pairs to reinforce lesson content.
Lesson Review Questions
Have students answer the Review Questions listed at the end of the lesson in the FlexBook® student edition.
Lesson Quiz
Check students’ mastery of the lesson with Lesson 6.3 Quiz inCK-12 Physical Science for Middle School Quizzes and Tests.
Points to Consider
Reactive elements combine easily with other elements. This explains why they usually exist in nature in compounds rather than in pure form.
• How do you think elements join together to form compounds?
• Do you think this might vary from one group of elements to another?
www.ck12.org
C HAPTER
7 TE Chemical Bonding
Chapter Outline
7.1 CHAPTER7: CHEMICALBONDING
7.2 7.1 INTRODUCTION TOCHEMICALBONDS