Transcript holtchp14review - Marshall Middle School

Holt Chapter 14
Chapter Review
Using Vocabulary
• 1. The force of attraction that holds two
atoms together is a chemical bond.
• 2. Charged particles that form when
atoms transfer electrons are ions.
• 3. The force of attraction between the
nuclei of atoms and shared electrons is
a covalent bond.
• 4. Electrons free to move throughout a
material are associated with a metallic
bond.
• Shared electrons are associated with a
covalent bond.
Understanding Concepts
• 6. Which element has a full outermost
energy level containing only 2
electrons?
• a) oxygen b) hydrogen c) fluorine
• d) helium
• Answer: d) Helium
• 7. Which (of the following) describes
what happens when an atom becomes
an ion with a 2- charge?
• Answer: c) the atom gains 2 electrons
• 8. The properties of ductility and
malleability are associated with which
type of bonds?
• a) ionic b) covalent c) metallic d)
none of the above
• Answer: c) metallic
• 9. In which area of the periodic table do
you find elements whose atoms easily
gain electrons?
• Answer: c) on the right side
• 10. What type of element tends to lose
electrons when it forms bonds?
• A) metal b) metalloid c) nonmetal d)
noble gas
• Answer: a) metals
• 11. Which pair of atoms can form an
ionic bond?
• Answer:
• b) potassium (K) and fluorine (F)
Short Answers
• 12. List two properties of covalent
compounds.
• Answers could include:
• - a low melting point,
• - a low boiling point,
• - brittle when solid at room temp.
• 13. Explain why an iron ion is attracted to a
sulfide ion but NOT to a zinc ion?
• Answer: iron and zinc are metals that tend to
lose electrons , thus becoming positively
charged. They would repel each other.
• Sulfide ion is negatively charge sulfur atom
that gained electron, so is attracted to a
positively charge atom such as iron
• 14. Using knowledge of valence electrons,
explain why carbon is an element in so many
different molecules.
• Carbon has 4 valence electrons, therefore
can have 4 bonds, including other carbon
atoms. This is the most bonding possibilities.
Usually atoms with less than 4 valence
electrons give up electrons, and may only
have one bond.
• 15. Three types of bonds:
• Ionic - lose/gain electrons
• Covalent - share electrons
• Metallic - electrons can move between
ions within a metal
Concept map
• 16. This was put on the board
Critical Thinking
• 17. Types of bonding of these pairs:
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A) zinc + zinc = metallic
B) oxygen + nitrogen = covalent
C) phosphorus and oxygen = covalent
D) magnesium and chlorine = ionic
• 18. Dots & bonds
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A) sulfur (S); 6 dots, 2 bonds
B) nitrogen (N); 5 dots, 3
C) neon (Ne); 8 dots, 0 bonds
D) iodine (I); 7 dots, 1 bond
E) silicon (Si); 4 dots, 4 bonds
• 19. What type of bond does the picture
of a hammer is hitting a white, solid
object with little parts appearing on the
table represent.?
• Answer: The substance is brittle, and is
breaking into tiny pieces, therefore is an
ionic bond.
Math in Science
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20.Electrons gained/loss and charge
Answers:
A) calcium (Ca); lose 2 e-; 2 +
B) phosphorus (P); gain 3e-; 3 C) bromine (Br); gain 1e-; 1D) sulfur (S); gain 2e-; 2 -
Interpreting Graphics
• 21. The metal band near the eraser is
the part of the pencil where metallic
bonds are formed.
• 22. Molecules with covalent bonds in a
pencil include:
• - graphite
• - wood
• - eraser
• 23. Two differences between the properties of
the parts of the pencil are:
• Answer: The metallically bonded part of the
pencil is shiny, can be bent without breaking,
and is hard in texture;
• The covalently bonded parts are not shiny,
will break when bent, and are softer.
Example: eraser, graphite, wood
• The End