Pretest

1
Pretest
Chapter 5

• 1. Which of the following is a symbol for an
  element?
• a. Aluminumb. Alc. ald. AL
• 2. Is flammability a physical property or a
  chemical property?
• 3. What happens to the composition of matter
  during a physical change?

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Pretest (continued)
Chapter 5

• 4. What does the atomic number of an element
  represent?
• 5. Different isotopes of an element have
  different numbers of
• a. neutrons. b. electrons. c. protons.
  d. nuclei.

3
Pretest (continued)
Chapter 5

• 6. True or False Electrons in atoms occupy
  orbitals in energy levels.
• 7. Which element is more reactive, oxygen or
  nitrogen?

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Interest Grabber
Section 5.1

• A Logical Organization
• The ability to organize information in a logical
  way is a valuable skill. Have you ever noticed
  the way shoeboxes are arranged in a shoe store?
  Sometimes the shoeboxes are separated into a
  series of vertical stacks (or columns) by style.
  Within each stack, the shoes are arranged by
  size.
• 1. How is this system of organizing shoes
  useful?
• 2. Explain how a calendar organizes time.
• 3. Think of another example of how information
  is organized.

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Reading Strategy
Section 5.1

• Summarizing

a. Mendeleev arranged the elements in order of
increasing mass so that elements with similar
properties were in the same column. b.
Mendeleev used the properties of existing
elements to predict properties of undiscovered
elements. c. The close match between
Mendeleevs predictions and the actual properties
of new elements showed how useful his periodic
table could be.
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Mendeleevs Table of Elements (1872)
Figure 3
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Interest Grabber
Section 5.2

• Displaying Information About Elements
• For each element there are many useful pieces of
  information, such as its name, symbol, atomic
  number, and state at room temperature. Look at
  the information for the element copper. There are
  different ways to display this information. On a
  piece of paper, design a way to organize the
  information inside a small square. You can use
  devices such as color to help fit the information
  in the square. Think about how this square will
  fit in a table that includes all the elements.

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Reading Strategy
Section 5.2

• Previewing

a. and c. Students might ask the meaning of the
term atomic number, why two series of elements
are placed below the main body of the table, why
there are two numbering systems for the columns,
or why Period 7 is incomplete.
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Periodic Table of Elements
Figure 7
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Isotopes of Chlorine
Figure 9
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Interest Grabber
Section 5.3

• Other Periodic Tables
• Most periodic tables of the elements have the
  same general organization as the one in your
  textbook. However, there are some periodic tables
  that look quite different. Look at Theodore
  Benfeys version of a periodic table, which he
  made in 1960.
• 1. How is it similar to the periodic table
  in your book?
• 2. How is it different from the periodic table
  in your book?
• 3. Is there any advantage to Benfeys
  arrangement of the elements?

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Reading Strategy
Section 5.3
Monitoring Your Understanding
Possible answers a. Magnesium plays a key role
in the production of sugar in plants. Mixtures of
magnesium and other metals can be as strong as
steel, but much lighter.

• b. Aluminum is the most abundant metal in Earths
  crust. Much less energy is needed to purify
  recycled aluminum than to extract aluminum from
  bauxite.
• c. Chlorine is a highly reactive, nonmetal gas
  that is used to kill bacteria in water.

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Reading Strategy
Section 5.3
Monitoring Your Understanding
Possible answers a. Magnesium plays a key role
in the production of sugar in plants. Mixtures of
magnesium and other metals can be as strong as
steel, but much lighter.

• b. Aluminum is the most abundant metal in Earths
  crust. Much less energy is needed to purify
  recycled aluminum than to extract aluminum from
  bauxite.
• c. Chlorine is a highly reactive, nonmetal gas
  that is used to kill bacteria in water.

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Pretest Answers
Chapter 5

• 1. Which of the following is a symbol for an
  element?
• a. Aluminumb. Alc. ald. AL
• 2. Is flammability a physical property or a
  chemical property?
• 3. What happens to the composition of matter
  during a physical change?

a chemical property
It remains the same.
Click the mouse button to display the answers.
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Pretest Answers (continued)
Chapter 5

• 4. What does the atomic number of an element
  represent?
• 5. Different isotopes of an element have
  different numbers of
• a. neutrons. b. electrons. c. protons.
  d. nuclei.

the number of protons in an atom of the element
Click the mouse button to display the answers.
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Pretest Answers (continued)
Chapter 5

• 6. True or False Electrons in atoms occupy
  orbitals in energy levels.
• 7. Which element is more reactive, oxygen or
  nitrogen?

oxygen
Click the mouse button to display the answers.
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Interest GrabberAnswers
Section 5.1

• 1. How is this system of organizing shoes useful?
  
• This system makes it much easier for the
  salesperson to find the right shoe quickly.
• 2. Explain how a calendar organizes time.
• A calendar separates a year into months, then
  months into weeks, and then weeks into days.
• 3. Think of another example of how information is
  organized.
• Answers will vary, but may include a class
  schedule, train or bus schedule, or the aisles in
  a supermarket.

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Interest GrabberAnswers
Section 5.2

• Designs will vary, but students should include
  all the information supplied.

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Interest GrabberAnswers
Section 5.3

• 1. How is it similar to the periodic table in
  your book?
• Both tables have the elements arranged in order
  of increasing atomic number and in groups with
  similar properties.
• 2. How is it different from the periodic table in
  your book?
• In Benfeys table the elements are arranged in a
  spiral instead of columns and rows. Benfeys
  table contains no data except the symbols of the
  elements.
• 3. Is there any advantage to Benfeys arrangement
  of the elements?
• The lanthanides and actinides are more closely
  connected to the other elements and it is clearer
  that hydrogen has the atomic number 1. (The most
  significant advantage is that the spiral format
  shows the connection between periods and atomic
  structure.)

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Chapter 5
Go Online
Self-grading assessment Articles on
elements For links on the periodic table, go to
www.SciLinks.org and enter the Web Code as
follows ccn-1051. For links on periodic law, go
to www.SciLinks.org and enter the Web Code as
follows ccn-1052.
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