Bonding in Metals (pages 36–39)

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Name
Date
Atoms and Bonding
■
Class
Adapted Reading and Study
Bonding in Metals
Metallic Bonding
(pages 36–39)
(page 37)
Key Concept: A metal crystal consists of positively
charged metal ions embedded in a “sea” of valence
atoms.
• The physical and chemical properties of metals can be
explained by the structure of metal atoms and by the
bonding between them.
• Most metals have one, two, or three valence electrons.
Metals easily lose electrons. Metal ions have a positive
electric charge.
• Solid metals are crystals. Metal atoms in the crystal are
very close together. The atoms in a metal crystal are
arranged in a specific way.
• In a metal crystal, the atoms exist as positive ions. The
valence electrons lost from the ions freely drift around
the ions in the crystal. The metal ions are held in place
by metallic bonds. A metallic bond is the attraction
between a positive metal ion and the electrons
around it.
Answer the following questions. Use your textbook and the
ideas above.
1. Circle the letter of each sentence that is true about
metallic bonding.
a. Most metals have one, two, or three valence
electrons.
b. Metals easily lose protons.
c. Metal ions have a positive electrical charge.
© Pearson Education, Inc., publishing as Pearson Prentice Hall. All rights reserved.
18
Name
Date
Atoms and Bonding
■
Class
Adapted Reading and Study
2. What is the attraction between a positive metal ion and
the electrons around it? Circle the letter of the correct
answer.
a. ionic bond
b. covalent bond
c. metallic bond
Metallic Properties
(pages 37–39)
Key Concept: The “sea of electrons” model of solid
metals explains their ability to conduct heat and
electricity, the ease with which they can be made to
change shape, and their luster.
• Heat travels through metals easily because the valence
electrons are free to move. The increased motion of
warmer parts of the metal are easily passed by the
valence electrons to cooler parts of the metal.
• Electricity flows when charged particles are free to
move. Because the valence electrons in a metal crystal
are free to move, electricity can flow.
• You can easily change the shape of a metal because the
metal ions are not attracted to other ions. The ions are
attracted only to the loose valence electrons around
them. So, the ions can be pushed out of position.
• Because metal ions move easily, metals are ductile.
Ductile means that a metal can be bent easily and
pulled into a wire. Metals are malleable, too. Malleable
means that a metal can be rolled into thin sheets or
beaten into a shape.
• When light strikes valence electrons, the electrons
absorb the light and then give it off again. This makes
metals look shiny.
© Pearson Education, Inc., publishing as Pearson Prentice Hall. All rights reserved.
19
Name
Date
Atoms and Bonding
■
Class
Adapted Reading and Study
Answer the following questions. Use your textbook and the
ideas on page 19.
3. Is the following sentence true or false? Heat flows
easily through metals because the positive metal ions
are free to move.
4. Look at the pictures of the paper clip and the aluminum
pan. Circle the picture that shows that metal is ductile.
5. Read each word in the box. Use the words to complete
the concept map about metals.
Ductile
Heat
Luster
Malleable
Metals
are
conduct
Shiny
c.
a.
Electricity
b.
© Pearson Education, Inc., publishing as Pearson Prentice Hall. All rights reserved.
20
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