1. Essential Question: How are elements arranged on the periodic table?
Unit 3 Lesson 2
Essential Question: How are elements arranged on the periodic table?
Copyright © Houghton Mifflin Harcourt Publishing Company

2. Metals/métal
Metalloids/
métalloïde
Nonmetals/non-métaux

4. Targets
Identify the atomic number, chemical symbol, name, and average atomic mass of an element on the periodic table.
Compare and contrast the properties of metals, nonmetals and metalloids.
Describe the arrangement of elements in groups and periods on the periodic table.

5. Get Organized! What are elements? p170
Unit 3 Lesson 2 The Periodic Table pg. 170
Get Organized!
What are elements?
By the 1860s, scientists considered there to be at least 60 different basic substances, or elements.
Scientists found that many of these elements have similar properties and began classifying them. 5

6. Get Organized! What are elements? P170 dull, nonmetal, brittle, odor/
Unit 3 Lesson 2 The Periodic Table pg. 170
Get Organized!
What are elements?
dull, nonmetal, brittle, odor/
terne, non métallique, fragile, odeur
Solid, shiny, metal/
Solide, brillant, en métal
gas, nonmetal, yellow/
gaz, non métallique, jaune
liquid, shiny, metal/
liquide, brillant, métal
metal, shiny/
métal, brillant
Liquid, nonmetal/
Liquide, non métallique 6

7. How are the elements organized?
p171
Unit 3 Lesson 2 The Periodic Table pg. 171
How are the elements organized?
Dmitri Mendeleev first organized the elements by arranging them in order of increasing atomic mass.
He observed that the properties of those elements were in a periodic, or regularly repeating, pattern. 7

8. How are the elements organized?
p171
Unit 3 Lesson 2 The Periodic Table
How are the elements organized?
Mendeleev’s arrangement of the elements became known as the periodic table.
Henry Moseley reorganized Mendeleev’s periodic table in order of increasing number of protons, or atomic number.
The periodic table is useful because it makes clear many patterns among the elements’ properties.
6) Explain
Henry Moseley arranged the elements on the periodic table in order of increasing atomic number 8

9. How are the elements organized?
Unit 3 Lesson 2 The Periodic Table pg
How are the elements organized?
8) 3
9) 6 9

10. p174
Unit 3 Lesson 2 The Periodic Table pg. 174
Making Arrangements
What information is contained in each square on the periodic table?
Each square contains an element’s chemical name, atomic number, chemical symbol, and average atomic mass.
The atomic number is placed at the top of each square.
The chemical symbol is an abbreviation for the element’s name.
The first letter of the chemical symbol is always capitalized, and any other letter is lowercase.
The name of the element is written under the symbol.
Copyright © Houghton Mifflin Harcourt Publishing Company 10

11. What information is contained in each square on the periodic table?
Unit 3 Lesson 2 The Periodic Table pg. 174
What information is contained in each square on the periodic table?
All atoms of an element have the same number of protons, but the number of neutrons can vary.
The average atomic mass of an atom is the weighted average of the masses of all the naturally occurring isotopes of that element.
Average atomic mass is reported in atomic mass units (u).
Copyright © Houghton Mifflin Harcourt Publishing Company 11

12. Targets
Identify the atomic number, chemical symbol, name, and average atomic mass of an element on the periodic table.
2. Compare and contrast the properties of metals, nonmetals and metalloids.

13. How are the elements arranged on the periodic table?
Unit 3 Lesson 2 The Periodic Table pg. 175
How are the elements arranged on the periodic table?
A zigzag line on the periodic table divides the three major categories of elements: metals, nonmetals, and metalloids.
Metals are elements that are shiny and conduct heat and electricity well.
Elements to the left of the zigzag line are metals, except for hydrogen.
Copyright © Houghton Mifflin Harcourt Publishing Company 13

14. How are the elements arranged on the periodic table?
Unit 3 Lesson 2 The Periodic Table pg. 175
How are the elements arranged on the periodic table?
The elements to the right of the zigzag line are nonmetals.
Nonmetals are poor conductors of heat and electricity, and are often dull and brittle.
Metalloids are elements that have some properties of metals and nonmetals. They border the zigzag line.
Copyright © Houghton Mifflin Harcourt Publishing Company 14

15. Nonmetal/ Metal/métal Metalloid/ non-métal métalloïde
Unit 3 Lesson 2 The Periodic Table pg. 175
Nonmetal/
non-métal
Metal/métal
Metalloid/
métalloïde

16. Shiny/ Dull and Brittle/ Brillant Along Staircase/
Terne et cassant
Shiny/
Brillant
Along Staircase/
Le long de l'escalier
Conduct heat and electricity well/
Conduire bien la chaleur et l'électricité
Right side of staircase/
Côté droit de l'escalier
Metals/Les métaux
Metalloids/
Métalloïdes
Nonmetals/
Non-métaux
Have metallic and nonmetallic properties/
Avoir des propriétés métalliques et non métalliques
Left side of P.Table EXCEPT for Hydrogen/
Côté gauche de P.Table SAUF pour Hydrogène
Poor conductors of heat and electricity/Mauvais conducteurs de chaleur et d'électricité

17. Targets
Identify the atomic number, chemical symbol, name, and average atomic mass of an element on the periodic table.
Compare and contrast the properties of metals, nonmetals and metalloids.
Describe the arrangement of elements in groups and periods on the periodic table.

18. How are the elements arranged on the periodic table?
Unit 3 Lesson 2 The Periodic Table
How are the elements arranged on the periodic table?
Each vertical column of elements on the periodic table is called a group, or family.
Elements in a group are similar because their atoms have the same number of valence electrons.
Valence electrons participate in chemical bonding. 18

19. How are the elements arranged on the periodic table?
Unit 3 Lesson 2 The Periodic Table
How are the elements arranged on the periodic table?
List three metals, nonmetals, and metalloids.
Copyright © Houghton Mifflin Harcourt Publishing Company 19

20. How are the elements arranged on the periodic table?
Unit 3 Lesson 2 The Periodic Table
How are the elements arranged on the periodic table?
Each horizontal row of elements on the periodic table is called a period.
Physical and chemical properties of elements change in predictable ways from one end of the period to the other.
Elements in the same period have the same number of energy levels 20

21. Atomic number increases as you move from left to right
Number of energy levels increase by 1 as you go down the periodic table
Number of Valence Electrons increase and you go from left to right on the periodic table
Atomic size decreases as you move from left to right across a period.

23. Lab

24. Lab 2) Describe the pattern you see in the graph
The line drops steadily and then jumps and begins to drop again in a diagonal line pattern
3) Compare your graph to the periodic table of elements. How does the pattern relate to the structure in the periodic table?
The diagonal line in the graph relate to the periods (rows) in the periodic table.
Each jump in the line marks the beginning of a new period (row) in the periodic table
4) What trends to you observe about the relationship between atomic radius and the atomic number?
The value for atomic radii generally decrease across a period as atomic number increases
5) Based on the trends, what are approximate values of the atomic radii of 10, 18, and 31
(approximately) 50, 90, 150

25. Same number of valence electrons
Same number of energy levels or shells 17 2 3 3 7 17

26. 2 3 1 6
group
period
Atomic Number
Protons
Valence electrons
Energy levels (shells)
Down
Vertical
Across
Horizontal

27. SWS 3 Assignments Due by Wednesday 11/1
Groups and Periods: Conclusions and Applications
Understanding the Periodic Table
Predicting Properties Lab
Lesson Review pg 179 #1-9, #10 Extra Credit
EVERYONE MUST TURN IN KEY TERMS!
This does NOT count as one of the assignment due

28. Unit 3 Lesson 2 review pg. 179 #1-10
Metal
Nonmetal
Metalloid
An element that has properties of both metals and nonmetals
An element that is shiny and that conducts heat and electricity well
An element that conducts heat and electricity poorly

29. Unit 3 Lesson 2 review pg. 179 #1-10
4. Identify 5. Identify 6. Describe
7. Apply
Group or Family 90 Th
Period
Thorium
The zigzag or “staircase” on the periodic table separates the metals and nonmetals
232.04

30. Unit 3 lesson 2 review pg. 179 #1-10
8 Infer
Atoms of copper and silver have the same number of valence electrons
9 Apply
The nucleus of a copper atom contains one more proton than the nucleus of a nickel atoms

31. Unit 3 lesson 2 review pg. 179 #1-10
10 Explain
The elements are arranged in order of increasing atomic number. Sulfur (S) has an atomic number of 16, and chlorine (Cl) has an atomic number of 17. There is no whole number between these two numbers, so an element cannot appear between sulfur (S) and chlorine(Cl).

32. Alternative Assessment due by Friday 11/3