Chapter 6

Multiple Choice

Identify the letter of the choice that best completes the statement or answers the question.

____          1.   A mutual electrical attraction between the nuclei and valence electrons of different atoms that binds the atoms together is called a(n)

a.	dipole.	c.	chemical bond.
b.	Lewis structure.	d.	London force.

____          2.   A chemical bond results from the mutual attraction of the nuclei of atoms and

a.	electrons.	c.	neutrons.
b.	protons.	d.	dipoles.

____          3.   The electrons involved in the formation of a chemical bond are called

a.	dipoles.	c.	Lewis electrons.
b.	s electrons.	d.	valence electrons.

____          4.   The electrostatic attraction between positively charged nuclei and negatively charged electrons permits two atoms to be held together by a(n)

a.	chemical bond.	c.	neutron.
b.	London force.	d.	ion.

____          5.   In a chemical bond, the link between atoms results from the attraction between electrons and

a.	Lewis structures.	c.	van der Waals forces.
b.	nuclei.	d.	isotopes.

____          6.   As independent particles, atoms are

a.	at relatively high potential energy.	c.	very stable.
b.	at relatively low potential energy.	d.	part of a chemical bond.

____          7.   Atoms are ____ when they are combined.

a.	more stable	c.	not bound together
b.	less stable	d.	at a high potential energy

____          8.   Atoms naturally move

a.	toward high potential energy.	c.	toward less stability.
b.	toward low potential energy.	d.	away from each other.

____          9.   As atoms bond with each other, they

a.	increase their potential energy, thus creating less-stable arrangements of matter.
b.	decrease their potential energy, thus creating less-stable arrangements of matter.
c.	increase their potential energy, thus creating more-stable arrangements of matter.
d.	decrease their potential energy, thus creating more-stable arrangements of matter.

____          10.  A chemical bond resulting from the electrostatic attraction between positive and negativeions is called a(n)

a.	covalent bond.	c.	charged bond.
b.	ionic bond.	d.	dipole bond.

____          11.  The chemical bond formed when two atoms share electrons is called a(n)

a.	ionic bond.	c.	Lewis structure.
b.	orbital bond.	d.	covalent bond.

____          12.  If two covalently bonded atoms are identical, the bond is

a.	nonpolar covalent.	c.	nonionic.
b.	polar covalent.	d.	coordinate covalent.

____          13.  When atoms share electrons, the electrical attraction of an atom for the electrons is called the atom's

a.	electron affinity.	c.	resonance.
b.	electronegativity.	d.	hybridization.

____          14.  If the atoms that share electrons have an unequal attraction for the electrons, the bond iscalled

a.	nonpolar.	c.	ionic.
b.	polar.	d.	dipolar.

____          15.  The electrostatic attraction between ____ forms an ionic bond.

a.	ions	c.	electrons
b.	dipoles	d.	orbitals

____          16.  A covalent bond results when ____ are shared.

a.	ions	c.	electrons
b.	Lewis structures	d.	dipoles

____          17.  Most chemical bonds are

a.	purely ionic.	c.	partly ionic and partly covalent.
b.	purely covalent.	d.	metallic.

____          18.  Nonpolar covalent bonds are not common because

a.	one atom usually attracts electrons more strongly than the other.
b.	ions always form when atoms join.
c.	the electrons usually remain equally distant from both atoms.
d.	dipoles are rare in nature.

____          19.  Purely ionic bonds do not occur because the atom that gives up an electron in such a bond

a.	is not an ion.
b.	still has some attraction for the electron.
c.	has a negative charge.
d.	shares the electron equally with the other atom in the bond.

____          20.  The greater the electronegativity difference between two bonded atoms, the greater the percentage of

a.	ionic character.	c.	metallic character.
b.	covalent character.	d.	electron sharing.

____          21.  Bonds that are between 5% and 50% ionic are considered

a.	ionic.	c.	polar covalent.
b.	pure covalent.	d.	nonpolar covalent.

____          22.  Bonds that are more than 50% ionic are considered

a.	polyatomic.	c.	ionic.
b.	polar covalent.	d.	nonpolar covalent.

____          23.  A bond that is less than 5% ionic is considered

a.	polar covalent.	c.	nonpolar covalent.
b.	ionic.	d.	metallic.

____          24.  The pair of elements that forms a bond with the least ionic character is

a.	Na and Cl.	c.	O and Cl.
b.	H and Cl.	d.	Br and Cl.

Short Answer   
144.            Why do most atoms form chemical bonds?
145.            Explain why scientists use resonance structures to represent some molecules.
146.            Differentiate between an ionic compound and a molecular compound.
147.            Explain what is meant by the lattice energy of BeF₂.
Problem 
148.            Draw a Lewis structure for the oxalate ion, C₂O₄^2–.
149.            Draw a Lewis structure for the ammonium ion, NH₄⁺.
150.            Draw a Lewis structure for the nitrate ion, NO₃^–.                 
151.            Draw a Lewis structure for the sulfate ion, SO₄^2–.

152.            Draw a Lewis structure for the phosphate ion, PO₄^3–.

Essay

   153.            List the six basic steps used in drawing Lewis structures.