KEY
Vocabulary: Define the following. See your notes and flashcards!
1. Alloy
2. Covalent bond
3. Metallic bond
4. Ionic bond
5. Ion
6. Electronegativity
7. Dipole
8. Polar compound
9. Non-polar covalent bond
Multiple Choice: Place the word or words that best complete the statement in the blank.
1.
2.
3.
4.
5.
6.
7.
8.
An atom that has either lost or gained one or more electrons is called a(n) ion.
Steel is an example of a(n) alloy.
Any compound bound by 2 oppositely charged atoms is called a ionic compound.
An atom that has lost electrons has a(n) positive charge.
At atom that has gained electrons will have a (n) negative charge.
A(n) ionic bond is the attraction between 2 oppositely charge atoms
A(n) covalent bond is the bond formed when 2 elements share electrons.
When one side of a molecule is slightly positive and one side is slightly negative the resulting molecule
is called a(n) dipole.
9. When the electronegative sides of 2 atoms in a molecule are not equal a(n) polar (covalent) molecule
is formed.
Free Response: Read each question carefully.
1. From where on the periodic table do atoms that form ionic bonds come? Far left and far right
2. What type of atoms form covalent bonds? Adjacent non-metals
3. Why do atoms bond with one another? (2 reasons) to fill their outer electron shells, to become
more stable
4. Give an example of an ionic compound. NaCl
5. Give an example of an ionic crystal. Table salt (NaCl), sugar, diamond
6. Give an example of an alloy. Steel, stainless steel, bronze, sterling silver, white carat gold
7. Give an example of a very common polar covalent molecule. water
8. Which group on the periodic table does not form bonds? Why not? Noble gases, outer shell full
9. Draw a molecule made of hydrogen and carbon atoms. Answer the questions below.
Be sure to include:
o correct # 0f C atoms
Hints: Each atom needs a full outer shell of e-s.
o correct number of H atoms
There are no double or triple bonds.
o correct number of bonds
A. Is the element you drew ionic, covalent, or metallic? ionic
B. Is the molecule you drew a dipole or a non-polar molecule? non-polar
H
H
C
H
There is more to the review! Press on bravely!
H
10. Why do we make alloys? They are harder than a single metal
11. Which one has a higher boiling point, a polar or a non-polar molecule? Why?
Polar , negative part of one molecule is attracted to the positive part of another
12. Using complete sentences, explain why a “tug of war” is a good analogy for remembering
how electronegativity works.
o What do the people in the competition represent?
o What does the rope represent?
o What does the strength of the people in the “tug of war” represent?
The people are atoms, pulling on electrons
The rope is a bond.
The strength of the people represents the electronegativity of each atom.
Fill in the blank:
Use the element below to answer questions.
5
B
10.81
1.
2.
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4.
This element has 5 protons.
This element has 5 electrons.
This element has 3 valence electrons.
This element needs ___5__electrons to fill its outer shell.