Physical Science 2 Test 2
Name ________________________________________________
1. Draw Lewis electron dot structures for the following ionic compounds. (3 pts)
a. MgS
b. CaCl2
c. Na3N
2. i) Draw Lewis electron dot structures for the following covalent compounds. (2 points)
ii) Determine the Shape
iii) Determine whether the molecule is polar or nonpolar (1point)
a. CF4
b. NH3
c. OF2
d. CS2
Match each item (a-o) with the correct statement below.
(NOTE: each item (a-o) may be used once, more than once, or not at all).
a.
b.
c.
d.
e.
cation
anion
electrostatic force
electronegativity
dipole (polar molecule)
f.
g.
h.
j.
k.
ionic bond
polar covalent bond
nonpolar covalent bond
intramolecular force
intermolecular force
10 points
l. Van der Waals force
m. London dispersion force (LDF)
n. dipole-dipole interaction (DDI)
o. hydrogen bond (HF)
____ 3. the force of attraction between a positive and negative charge
____ 4. atom or group of atoms having a positive charge
____ 5. intermolecular force between molecules that have permanent dipoles that are attracted to each other
____ 6. the relative ability of a bonded atom of an element to attract the electrons from the another element participating
in the bond.
____ 7. a molecule that has two electrically charged regions (a slightly positive region and a slightly negative region)
____ 8. these forces are present in all molecules, whether they are polar or nonpolar.
____ 9. the electrostatic force of attraction binding oppositely charged ions together
____ 10. a covalent bond between two atoms of significantly different electronegativities – (bonding occurs when the
electrons are shared unequally.)
____ 11. atom or group of atoms having a negative charge
____ 12. a covalent bond between atoms where the bonding electrons are shared equally.
____ 13. intermolecular force from an temporary dipole. (Caused by the motion of the electrons)
____ 14. this type of intermolecular force is found between molecule of water (H2O)
____ 15. the dipole-dipole interactions experienced between molecules when H is bonded to N, O, or F
____ 16. in a polar covalent bond, the atom with the higher ___________ will become partially negative
Identify each of the following as either intermolecular or intramolecular
4 points
17) _____________ Polar Covalent Bond
20) _____________ Covalent Bond
18) _____________ Hydrogen Bond
21) _____________ Dipole-Dipole Interact
19) _____________ London Dispersion
22) _____________ Van der Waals
23) For each box below, identify (label) the intermolecular and intramolecular attractions
4 points
____ 24) Which of the following covalent bonds is the most polar?
a. H—F
b. H—C
c. H—H
d. H—N
____ 25) Which of the following atoms acquires the most negative charge in a covalent bond with hydrogen?
a. C
b. N
c. O
d. S
____ 26) Which of the forces of molecular attraction is the weakest?
a. dipole-dipole interaction b. London dispersion c. hydrogen bond
d. single covalent bond
____ 27) Why do atoms share electrons in covalent bonds?
a. to become ions and attract each other
c. to become more polar
b. to gain a higher electronegativity
d. to attain a full valence energy level
____ 28) A bond formed between a silicon atom and an oxygen atom is likely to be ____.
a. ionic
b. coordinate covalent
c. polar covalent
d. nonpolar covalent
____ 29) What is thought to cause the London dispersion forces?
a. attraction between ions
c. sharing of electron pairs
b. motion of electrons
d. differences in electronegativity
Identify the primary type of Van der Waals Forces that exist between each type of molecule:
LDF = London Dispersion Forces, DDI = Dipole-Dipole Interaction, HB = Hydrogen Bonds
30)
C2H5OH- ______
31)
CH3Br- ______
32)
HI-
______
33)
CCl4-
______
34)
CH3NH2 -______
35)
CO2-
______
36)
Ar-
______
37)
HF -
______
38)
C2H4O - ______
39)
Br2-
______
10 points
40) List and explain the two factors that affect the force of attraction in London dispersion forces? 2 points
41) Explain how London dispersion forces cause molecules to be attracted to one another.
2 points
42) Rank the following FOUR molecules from lowest to highest boiling points: EXPLAIN
CH4
CBr4
CCl4
CF4
2 points
43) What is the difference between a hydrogen bond and a polar covalent bond involving hydrogen?