Name___________________________________________
Veritas _______________________Class Period ________
Chemistry: Final Exam Practice Problems
The final exam will focus on material covered in the spring semester. However, note that much of the
material learned early in the year has carried over into these units. This review guide is the minimum
of what should be completed in preparation for the final. Review old quizzes, tests, review guides,
and worksheets.
What are the seven diatomic elements?
Find the molar mass of the following:
a. KNO3
d. oxygen gas
b. (NH4)2CO3
e. Ca(NO3)2
Convert from g à moles or from moles à g. Show units and correct SFs.
a. 0.476 g of (NH4)2SO4 x
b. 0.15 moles NaNO3 x
=
=
moles
g
How did JJ Thomson conclude that the mobile charged particle in the
atom had a (–) charge.
Below left is a 2-D array that represents an ionic solid. At right is a 2-D
array that represents a molecular solid. Discuss at least four
differences between ionic and molecular substances.
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Which combinations of elements give rise to ionic compounds and which
form molecular compounds? (In other words, how do you recognize,
based on a formula alone, whether a compound is ionic or molecular?)
Write M for molecular compounds and I for ionic compounds. Then, write
the correct name for the compound.
PBr3
CO2
KOH
FeCl3
Hg(OH)2
Cu2O
Identify the following compounds as ionic or molecular. Provide the
correct formula for each compound.
Ionic or Molecular
Name
A. diphosphorous pentoxide_
B. ammonium nitride
C. calcium oxalate
D. potassium oxide
E. tin (IV) bromide
F. mercury (I) bromide
Define/Discuss the following terms:
Coefficients
Subscripts
Endothermic
Exothermic
Conservation of Mass
Aqueous solution
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Directions: Balance the following chemical reactions (including state
subscripts) and then provide the type of chemical reaction.
Oxygen gas plus nitrogen gas reacts to form nitrogen dioxide gas
Aqueous beryllium iodide reacts with aqueous tin (II) nitrate to form aqueous
beryllium nitrate and solid tin (II) iodide.
Aqueous ammonium sulfate reacts with aqueous lead (II) chlorate to form aqueous
ammonium chlorate and solid lead (II) sulfate.
Aqueous hydrogen carbonate decomposes to give liquid water and carbon dioxide
gas.
Liquid water reacts with carbon monoxide gas to produce hydrogen gas and carbon
dioxide gas.
Directions: Determine for each of the following reactions if the reaction is
endothermic or exothermic. Balance the equations.
____C + ___O2
___CO + energy
___N2O4 + energy
___CaCl2 + ___O2
___N2 + ___O2
___CaO + __Cl2 + energy
___SO2 + __CO2 + energy
___SO3 + __ CO
Type _______________
Type _______________
Type_______________
Type ________________
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Directions: Balance the following chemical reactions. If no reaction
occurs, write “no reaction.”
Solid zinc metal is placed into an aqueous solution of silver nitrate.
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Heptane (C7H16) burns readily in the presence of air.
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Aqueous calcium chloride is mixed with sulfuric acid.
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Phosphorus trichloride decomposes when heated strongly in a test tube.
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Directions: For each of the reactions below, write the balanced chemical
equation, including the energy term on the correct side of the equation.
Then represent the energy storage and transfer using the bar graphs.
When you heated sodium hydrogen carbonate, you decomposed it into sodium
oxide, water vapor, and gaseous carbon dioxide.
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When solid zinc was added to hydrochloric acid, the products were hydrogen gas
and an aqueous solution of zinc chloride. You could feel the test tube get hotter.
What observations did you note from the chemical reactions lab to identify if a
reaction occurred?
Draw a chemical potential energy curve for an exothermic reaction and for an
endothermic reaction.
Use balanced equation and the BCA table to predict the quantity of
reactant or product involved in a chemical reaction.
Calculate the number of grams of potassium chloride, KCl, that will be formed
by the decomposition of 6.45 g of potassium chlorate, KClO3.
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Determine percent yield when actual yield is known.
A chemist burns 160 g of Al in air to produce 260 g of solid aluminum oxide.
Determine the theoretical yield. Determine the percent yield.
Determine the limiting reactant and stoichiometry
Phosphorus and bromine react vigorously together to form phosphorus
tribromide. If 5.0 g of phosphorus and 35 g of bromine react, how many grams of
PBr3 could be produced?
Stoichiometry involving gases
Nitrogen gas and hydrogen gas combine to produce ammonia gas. What volume
of hydrogen gas at STP is required to react completely with 1.50 moles of
nitrogen gas?
Consider the following reaction:
P4(s) + 6 H2(g) → 4 PH3(g)
What volume of hydrogen gas at laboratory conditions of 25.0°C and 0.981 atm is
required to react completely with 42.85 grams of P4 ?
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Stoichiometry involving solutions
What is the molarity of a solution that contains 125 grams of NaCl in 4.00 L of
solution?
Solid iron (III) chloride can be produced by reacting aqueous iron (III) oxide with
a hydrochloric acid solution. How many milliliters of a 6.00M HCl solution are
needed to react with excess Fe2O3 to produce 16.5 grams of solid FeCl3? (NOTE:
The second product is liquid water.)
Calculate the ppm for the following problems:
a. 2.50 grams of solute dissolves in 3,500,000 grams of water.
b. 4.01 x 10-3 grams of salt is in 675,000 grams of water.
c. 5.00 mg of lead is in 2.00 kg of water.
Solubility Curve Problems:
Which is more soluble NaNO3 or KCl?_____________________________________
How does the line drawn for a particular substance relate to the saturation of a
solution of that substance?_______________________________________________
________________________________________________________________________
________________________________________________________________________
How many grams of NH4Cl will dissolve in 100 grams of 90°C
water?_______________
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Stoichiometry Including Energy Changes (ΔH)
Solid tin metal reacts with chlorine gas forming liquid tin (IV) chloride
according to the reaction shown below:
Sn (s)
+
2Cl2 (g)
à
SnCl4 (l)
ΔH = -511 kJ
What volume of chlorine gas (at laboratory conditions of 760.0 mm Hg and
25oC) is required in order for the reaction to release 328 kJ of heat energy?
Draw and label Thomson's "Plum-pudding" Model of the atom and
Rutherford's Model of the Atom. Compare and contrast the two models.
How did Rutherford come to his conclusion?
How did Niels Bohr improve Rutherford's model of the atom? Discuss
the changes. Draw Bohr's model of the atom.
Periodicity:
Explain/Discuss the periodic trends in atomic radii and ionization energy.
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Measurement and Calculations:
1. Demonstrate understanding of the use of measurements in science.
-You should be able to apply the rules of significant figures to choose answer
with the correct number of significant figures.
-Express the answer in the correct number of significant figures. Label with
appropriate units.
a. 21.3 g = 16.384615
1.3 cm3
b. 6.34 cm2 x 1.2 cm
1.217 cm
= 6.251437
c. 13.21m + 61.5 m = 74.71
You should also be able to measure the length of an object or volume of a liquid to
the appropriate number of significant figures based upon the measuring
instrument.
Which of the following best expresses the width of the business card?
a. 5 cm
b. 5.0 cm
c. 5.05 cm
d. 5.50 cm
Demonstrate proficiency in the use of scientific notation and use of dimensional
analysis in metric conversions.
-Know the meaning of the following metric prefixes and be able to make
conversions utilizing them: milli-, centi-, kiloExample:
1m
150mm ×
= 0.15m
1000mm
Complete the indicated conversions:
€
a. 37 g x
km
=
mg
c. 138 m x
b. 4.7 kg x
=
g
d. 4021 mm x
=
=
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