Honors Chemistry
Name
Chapter 10 Practice Quiz
Date _____/_____/_____
Period _____
1. 12,500 J of energy is added to 2.0 mol (36 g) of H2O as an ice sample at 0.0 oC. The molar heat of
fusion is 6.02 kJ/mol. The specific heat of liquid water is 4.18 J/mol ▪ K. The molar heat of
vaporization is 40.6 kJ/mol. The resulting sample contains which of the following?
a. liquid and gas
c. liquid
e. solid
b. solid and liquid
d. gas
Draw the graph and do calculations add up to more than 12,500. Where the energy exceeds that
amount is the line that it will end on.
2. Calculate the quantity of energy required to change 3.00 mol of liquid water to steam at 100 oC. The
molar heat of vaporization of water is 40.6 kJ/mol.
a. 122,000 J
c. – 2190 J
e. 13.5 J
b. 13,500 J
d. 122 J
3. Calculate the quantity of energy that must be released to change 26.5 g of steam to liquid water at
100 oC. The molar heat of vaporization of water is 40.6 kJ/mol.
a. – 1080 kJ
c. 1.53 kJ
e. 59.7 kJ
b. 27.6 kJ
d. – 59.7 kJ
4. The specific heat capacity of liquid water is 4.18 J/g ▪ oC. Calculate the quantity of energy required
to heat 1.00 g of water from 26.5 oC to 83.7 oC.
a. 460 J
c. – 13.3 J
b. 4310 J
d. 239 J
5. The specific heat capacity of liquid water is 4.18 J/ g ▪ oC. The molar heat of fusion is 6.02 kJ/mol.
Calculate the quantity of energy required to heat 10.0 g of ice from 0.0 oC to 83.7 oC.
a. 3340 J
c. 160 J
e. 6840 J
b. 3500 J
d. 1600 J
6. The molar heat of fusion of water is 6.02 kJ/mol. Calculate the energy required to melt 46.8 g of
water.
a. 1570 J
c. 15.7 kJ
e. 125 kJ
b. 282 kJ
d. 282,000 J
7. The molar heat of fusion of water is 6.02 kJ/mol. Calculate the energy released when 3.00 moles of
liquid water freezes.
a. 325 kJ
c. 3.00 kJ
b. – 18.1 kJ
d. 18.1 kJ
8. The molar heats of fusion of water and iodine are 6.02 kJ/mol and 16.7 kJ/mol, respectively. Which
will it take more energy to melt 1.00 gram of ice or 1.00 gram of solid iodine?
a. ice
c. both will melt at the same rate
b. iodine
d. neither
It takes more energy per gram to over come the forces of attraction for water than iodine.
9. The type of compound that is most likely to contain a covalent bond is
a. one that is composed of a metal from the far left of the periodic table and a nonmetal
from the far right of the periodic table
b. a solid metal
c. one that is composed of only nonmetals
d. held together by the electrostatic forces between oppositely charged ions
10. Lattice energy _______ as ionic radium increases and ______ as ionic charge increases.
a. decreases, increases
c. increases, increases
b. increases, decreases
d. decreases, decreases
11. Which one of the following ionic compounds would have the highest melting point?
a. K2O
b. KCl
c. CaCl2
d. MgO
In order to figure out which ionic compound will have the highest MP you one would have to look
at the oxidation numbers of the elements that are bonded. The greater difference in the oxidation
numbers the higher the MP. (K2O the K is +1 and the O is -2 (difference of 3), in the KCl the K is +1
and the Cl is -1 (difference of 2), CaCl2 the Ca is +2 and the Cl is -1 (difference of 3), MgO the Mg
is +2 and the O is -2 (difference of 4)). This affects the bond length which can be used to
determine the amount of energy need to break the bond.
12. In general, the distance between bonded atoms __________ as the number of shared electron
pairs increases.
a. increases
b. decreases
c. remains the same
13. Given that the average bond energies for C–H and C–Br bonds are 413 kJ/mole and 276 kJ/mole,
respectively, calculate the heat required to turn bromoform, CHBr3, into individual atoms.
a. 1241 kJ/mole
c. –689 kJ/mole
e. –1378 kJ/mole
b. 689 kJ/mole
d. 1378 kJ/mole
14. Of the bonds CN (single bond), CN (double bond), CN (triple bond), the CN (single bond) is
a. strongest/shortest
d. weakest/longest
b. strongest/longest
e. intermediate in both strength and length
c. weakest/shortest
15. The direct conversion of a solid to a gas is called
a. fusion
c. condensation
b. vaporization
d. boiling
e. sublimation
16. Which of the following is an exothermic process?
a. melting
c. freezing
b. subliming
d. boiling
Exothermic processes occur when energy is given off. Energy is given off when one is going
from right to left on the graph (or down).
17. As vapor pressure increases, boiling point _____ and volatility ______________.
a. decreases, increases
d. decreases, decreases
b. increases, decreases
e. decreases, remains constant
c. increases, increases
18. Increasing the total pressure above a liquid will cause the boiling point of the liquid to
a. increase
c. remain the same
b. decrease
d. depends on the liquid
19. On a phase diagram (Pressure vs. Temperature), the
a. critical point is that beyond which gas and solid are indistinguishable
b. triple point is that at which solid, liquid, and gas are in equilibrium
c. solid is generally found at high temperature and low pressure
d. liquid is generally found at high temperature and low pressure
e. both A and B
20. On the diagram below, which curve corresponds to the conditions of temperature and
pressure under which the solid and the gas of the substance are in equilibrium?
a. A
c. C
e. E
b. B
d. D
f. F
21. On the diagram above, the coordinates of point ____ correspond to the critical temperature and
pressure.
a. A
c. C
e. E
b. B
d. D
f. F
22. Which portion of below diagram corresponds to the gas phase?
a. w
b. x
c. y
d. z
23. What is the normal boiling point of this substance?
a. -3
b. 10
d. 30
c. 25
24. The difference between crystalline and amorphous solids is determined by
a. temperature changes.
b. pressure when the substances are formed.
c. amount of order in particle arrangement.
d. strength of molecular forces.
Crystalline solids have a regular arrangement of particles.
Amorphous solids have a random arrangement of particles.
25. Compared with a crystalline solid, the particles in an amorphous solid
a. occur in a random pattern.
b. occur in a definite, three-dimensional arrangement.
c. consist of molecular sheets.
d. have a more complex unit cell.
26. Which substance's solid state consists of covalent molecular crystals?
a. salt
b. water
c. sodium
d. diamond
Salt is ionic. Sodium is metallic. Diamond is network covalent. Water is the only substance
listed that would form a structure that is a molecular solid.
27. Which type of crystal consists of positive metal cations surrounded by valence electrons that are
donated by the metal atoms and belong to the crystal as a whole?
a. ionic
c. metallic
b. covalent network
d. covalent molecular
28. The triple point of a substance is the temperature and pressure conditions at which
a. density is greatest.
b. states of a substance coexist at equilibrium.
c. equilibrium cannot occur.
d. kinetic energy is at a minimum.
29. Above the critical temperature, a substance
a. does not have a vapor pressure.
b. sublimes.
c. cannot exist in the liquid state.
d. is explosive.
30. According to the figure below, what is the most volatile substance shown?
a. benzene
b. water
c. toluene
31. Whenever a liquid changes to a vapor, it
a. absorbs energy from its surroundings.
b. is in equilibrium with its vapor.
Use the figure below to answer the following questions.
d. aniline
c. is boiling.
d. is condensing.
32. What do points E and F represent in the figure above? (E = normal FP and F = normal BP)
33. What does point A represent in the figure above? (the triple point)
34. Explain what the curves AB, AC, and AD represent in the figure above. The solid/liquid line
represents the change if the density of the substance as the temperature is decreased and
the pressure is increased. The liquid/gas represents the change in density of the substance
as the temperature and pressure are increased.
35. Given that benzoic acid has a molar mass of 122.1 g/mol and a 52.9 g sample of benzoic acid
absorbs 7.83 kJ when it melts,
a. calculate the number of moles in the sample. 0.433 moles
b. calculate the molar enthalpy of fusion of benzoic acid. 18.1 kJ/mole
36. Given that water has a molar enthalpy of vaporization of 40.79 kJ/mol, how many grams of water
could be vaporized by 623 J? 0.275 g
Use the following to answer questions 37 – 40: (Some of the questions can have more than one answer.)
a. Ionic Solid
b. Molecular solid
c. Metallic Solid
d. Covalent Network Solid
37. Which of the above are good conductors of heat and electricity? c
38. Which of the above would be classified as hard and brittle? a, d
39. Which of the above will not dissolve in water? c, d
40. Which of the above can be classified as either polar or nonpolar? b
Use the following to answer classify the given substances in questions 42 – 45:
a. covalent network solid
b. metallic solid
41.
42.
43.
44.
CaBr2
I2
SiC
Zn(s)
d.
c.
a.
b.
c. molecular solid
d. ionic solid
ionic solid
molecular solid
covalent network solid
metallic solid
45. 8 carat gold, which is composed of 47% copper, 33% gold, and 20 % silver, is an example
of what type of alloy?
a. superficial
c. metallic
b. interstitial
d. substitutional
46. Which of the following is an example of an interstitial alloy?
a. steel
c. silicon dioxide
b. copper
d. brass
47. What is the meaning of “Like Dissolves Like”?
a. polar substances dissolve in nonpolar solvents
b. nonpolar substances dissolve in nonpolar solvents
c. polar substances dissolve in polar solvents
d. both b and c
48. The normal boiling point of a substance occurs at what pressure?
a. 760. mm Hg
c. 760. torr
b. 101.3 kPa
d. 1.00 atm
e. all of these
49. What two processes must exist in equilibrium when a measurement of vapor pressure is taken?
a. sublimation and deposition
c. boiling and condensing
b. freezing and melting
d. vaporization and condensation