Chemistry Assignment Sheet Semester 1 Review
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Due: Ch. 1 Problems: A2, A5a, A6a, A7a, A9a, A13a, A15d, C1b, C8a, D4,
D7, E1a,
Ch. 2 Problems: C3abc, C4, D6, D8.
In class: Sample Problems
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Due: Ch. 3 Problems: A3, B9, C2c, D8, E5abcd, G5, H2a.
In class: Sample Problems
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Due: Ch. 4 Problems: B2a, B3c, B3d, {molecular only: C3ab, D2c}, D3b, D4b,
E3e, E5c.
In class: Sample Problems
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Due: Ch. 5 Problems: A3a, B1, B3, B8a, C11b, C6, D3, E1a, E2a, E7.
In class: Sample Problems
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Due: Ch. 6 Problems: A2, A5, A6, C6, E3, D2, D3.
In class: Sample Problems
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Sample Problems in Class
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Multiple Choice Final Exam (40 questions, 200 pts)
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Written Final Exam (10 questions, 200 pts)
For Final Exam: You may use one 3”X 5” card, front and back.
-No worked out problems.
-It can have definitions, equations, constants, steps to work out problems.
-It must be handwritten (no computer, no Xeroxing).
Chemistry Semester 1 Review
Chemistry Ch. 1 Chemical Foundations
A2) How many significant figures are in each of
the following?
a) 12 b) 1098 c) 2001
d) 2.001 X103
e) 0.0000101 f) 1.01 X10-5 g) 1000.
h) 22.04030
A5) Perform the following mathematical
operations, and express each result to the correct
number of significant figures.
a) 97.381 + 4.2502 + 0.99195
A6) Perform the following mathematical
operations, and express each result to the correct
number of significant figures.
a) 0.102 X 0.0821 X 273
1.0
A7) Perform the following mathematical
operations, and express each result to the correct
number of significant figures.
a) 4.184 X 100.62 X (25.270 – 24.16)
A9) Perform each of the following conversions:
a) 8.43 cm to millimeters (mm)
A13) Perform the following unit conversions.
a) 908 oz to kilograms
A15) The world record for the hundred meter dash
is 9.79s.
a) Find the speed in m/s b) convert m/s to km/h
c) convert m/s to ft/s
d) convert m/s to mi/h
Hint: speed = distance / time = (100. m / 9.79 s)
C1) The density of aluminum is 2.70 g/cm3.
Express this value in
a) kilograms per cubic meter
b) pounds per cubic foot
C8) Find each volume, which in each pair has
greater volume? (Use the necessary densities, see
the Density Table.)
a) 100. g gold or 100. g water
D4) Classify each of the following as
homogeneous or heterogeneous:
a) copper b) Kool-Aid c) salt
d) orange juice with pulp
D7) Are the following changes chemical or
physical?
a) freezing water
b) your hand put into strong acid
c) insecticide sprayed on an insect
d) electricity conducted through a copper wire
E1) Convert the following Celsius temperatures
to Kelvin and to Fahrenheit.
a) The boiling point of ethyl alcohol is 78.1 oC.
Chemistry Ch. 2 Atoms, Molecules, and Ions
C3) Complete the following table:
Symbol #protons #neutrons #electrons charge
238
U
?
?
?
?
?
20p
20n
?
2+
?
23p
28n
20e
?
C4) Classify the following elements as metals,
nonmetals or metalloids:
Mg Si
Rn Bi
Ti
Ge Eu At
Au B
Am Br
D6) Name each of the following compounds:
c) CoI2
a) CuI
b) CuI2
d) Na2CO3 e) NaHCO3
f) S4N4
g) SF6
h) NaOCl (=NaClO)
i) BaCrO4 j) NH4NO3
D8) Write the formula for each of the following
compounds:
a) cesium oxide
b) potassium sulfate
c) ammonium chloride d) chlorine monoxide
e) silicon tetrachloride f) chlorine trifluoride
g) beryllium oxide
h) magnesium fluoride
Chemistry Ch. 3 Stoichiometry
A3) An element consists of 1.40% of an isotope
with mass 203.973 amu, 24.10% of an isotope
with mass 205.9745 amu, 22.10% of an isotope
with mass 206.9759 amu, and 52.40% of an
isotope with mass 207.9766 amu. Calculate the
average atomic mass and identify the element.
B9) Aspirin (acetylsalicylic acid, C9H8O4) is one
of the most commonly used pain relievers. A
typical tablet contains 500. mg of aspirin. How
many moles and molecules are in a 500. mg
tablet of aspirin?
Chemistry Ch. 3 Stoichiometry
C2) Calculate the percent composition by mass in
the following starting materials for synthetic
polymers (plastics).
c) C3H3N (acrylonitrile, from which Orlon is
made)
D8) Benzene contains only carbon and hydrogen
and is 7.74% H by mass. The molar mass is 78.1
g/mol. Determine the empirical and molecular
formulas of benzene.
D11) A compound contains only C, H, and N.
Combustion of 35.0 mg of the compound
produces 33.5 mg CO2 and 41.1 mg H2O. What is
the empirical formula of the compound?
E5) Balance the following equations and state the
type:
a) Cr(s) + S8(s) → Cr2S3(s)
b) heat + NaHCO3(s) → Na2CO3(s) + CO2(g) +
H2O(g)
(The “heat” can be ignored.)
c) heat +KClO3(s) → KCl(s) + O2(g)
d) Eu(s) + HF(g) → EuF3(s) + H2(g)
G5) A student prepared aspirin in the laboratory
experiment, reacting 1.50 g salicylic acid with
2.00g acetic anhydride. The experimental yield
was 1.50 g aspirin. Calculate the theoretical yield
of aspirin and the percent yield for this
experiment.
C7H6O3 + C4H6O3 → C9H8O4 + HC2H3O2
salicylic acetic
aspirin
acetic
acid
anhydride
acid
H2) Find the formula of the following hydrates:
a) 0.737 g MgSO3 and 0.763 g H2O
Chemistry Ch. 4 Types of Chemical Reactions
B2) Calculate the concentration of all ions present
in each of the following solutions of strong
electrolytes.
a) 0.100 mol of Ca(NO3)2 in 100.0 ml of solution
B3) Describe how you would prepare each of the
following solutions.
c) 2.00 L of 0.100 M K2CrO4 from solid K2CrO4
d) 2.00 L of 0.100 M K2CrO4 from 1.75 M
K2CrO4
C1) Write the balanced molecular equation,
complete ionic equation, and net ionic equation.
a) BaCl2(aq) + Na2SO4(aq) →
C3) Write the balanced molecular equation,
complete ionic equation, and net ionic equation.
a) AgNO3(aq) + KI(aq) →
b) CuSO4(aq) + Na2S(aq) →
D1) Write the balanced molecular equation,
complete ionic equation, and net ionic equation.
a) HClO4(aq) + Mg(OH)2(s) →
D2) Write the balanced molecular equation,
complete ionic equation, and net ionic equation.
c) Ca(OH)2(aq) + HCl(aq) →
D3) What volume of each of the following acids
will react completely with 50.00 ml of 0.200 M
NaOH?
a) 0.100 M HCl
b) 0.150 M HNO3
D4) What volume of each of the following bases
will react completely with 25.00 ml of 0.200 M
HCl?
a) 0.100 M NaOH
b) 0.0500 M Ba(OH)2
D6) Hydrochloric acid (75.0 ml of 0.250 M) is
added to 225.0 ml of 0.0550 M Ba(OH)2
solution. What is the concentration of excess H+
or OH- ions left in the solution? Will the final
solution be acidic, basic, or neutral?
E3) Balance the following oxidation-reduction
reactions that occur in acidic solution.
e) CH3OH(aq) + Cr2O72-(aq) → CH2O(aq) + Cr3+(aq)
E5) Balance the following redox reactions that
occur in basic solution.
c) NO2-1(aq) + Al(s) → NH3(g) + AlO2-1(aq)
Chemistry Ch. 5 Gases
A3)
a) If the open-tube
manometer has a height
difference of 118 mm
between the mercury levels
and the atmospheric pressure
is 760 torr, what is the
pressure of the gas in the
flask in torr, atmospheres and pascals?
B1) An aerosol can contains 400. ml of
compressed gas at 5.20 atm. When all the gas is
sprayed into a large plastic bag, the bag inflates to
a volume of
2.14 L. What is the pressure of the gas inside the
plastic bag? Assume temperature is constant.
B3) If 0.500 mol of nitrogen gas occupies a
volume of 11.2 L at 0oC, what volume will 2.00
mol of nitrogen gas occupy at the same
temperature and pressure?
B8) A 2.50 L container is filled with 175 g argon.
a) If the pressure is 10.0 atm, what is the
temperature?
C6) Air bags are activated when a severe impact
causes a steel ball to compress a spring and
electrically ignite a detonator cap. This causes
sodium azide (NaN3) to decompose explosively
according to the reaction:
2 NaN3(s) → 2 Na(s) + 3 N2(g)
What mass of NaN3(s) must be reacted in order to
inflate an air bag to 70.0 L of gas at STP?
C11) Silicon tetrachloride (SiCl4) and
trichlorosilane (SiHCl3) are both starting materials
for the production of electronics-grade silicon.
a) Calculate the density of pure SiCl4 vapor at
85oC and 758 torr.
b) Calculate the density of pure SiHCl3 vapor at
85oC and 758 torr.
D3) A sample of nitrogen gas was collected over
water at 20.oC and a total pressure of 1.00 atm. A
total volume of 2.50 X102 ml was collected. What
mass of nitrogen was collected, if at 20.oC the
vapor pressure of water is 17.5 torr?
E1) Calculate the average kinetic energy of the
CH4 molecules in a sample of CH4 gas at the
following temperatures.
a) 273 K b) 546 K
E2) Calculate the root mean square velocity of
the CH4 molecules in a sample of CH4 gas at the
following temperatures.
a) 273 K b) 546 K
E7) The rate of effusion of a particular gas was
measured and found to be 24.0 ml/min. Under
the same conditions, the rate of effusion of pure
methane, CH4, is 47.8 ml/min. What is the
molar mass of the unknown gas?
E10) Calculate the pressure exerted by 0.5000
mol N2 in a 10.00 L container at 25.0oC
a) using the ideal gas law.
b) using the Van der Waal equation.
c) Find the % error.
d) compare the % error with Problem E9 &
discuss.
Chemistry Ch. 6 Thermochemistry
A2) A gas absorbs 45 kj of heat and does 29 kj of
work. Calculate ΔE.
A5) Consider a mixture of air and gasoline vapor
in a cylinder with a piston. The original volume is
40. cm3. If the combustion of this mixture
releases 950. j of energy, to what volume, will the
gases expand against a constant pressure of 650.
torr, if all the energy of combustion is converted
into work to push back the piston?
A6) A balloon filled with 39.1 mol helium has a
volume of 876 L at 0.0oC and 1.00 atm pressure.
The temperature of the balloon is increased to
38.0oC as it expands to a volume of 998 L, the
pressure remaining constant. Calculate the q, w,
and ΔE for the helium in the balloon. (The molar
heat capacity of helium gas is 20.8 j/oC·mol.) B4)
The overall reaction in commercial heat packs can
be represented as
4 Fe(s) + 3 O2(g) → 2 Fe2O3(s) ΔH = -1652 kj/mol
c) How much heat is released, when 1.00 g iron is
reacted with excess O2?
C6) A 150.0 g sample of metal at 75.0oC is added
to 180.0 g of water at 15.0oC. The temperature of
the metal and water go to 18.3 oC. Calculate the
specific heat of the metal.
C8) A 78.9 g sample of zinc metal is heated to
100.0oC and added to 234 ml of water at 22.0oC.
Calculate the final temperature of the zinc and
water, if the specific heat capacity of zinc is 0.388
j/g·oC. {Density of water is 1.00 g/ml.}
D2) Given the following data:
C2H2(g) + 5/2 O2(g) → 2 CO2(g) + H2O(l)
ΔH = -1300. kj
ΔH = -394 kj
C(s) + O2(g) → CO2(g)
H2(g) + 1/2 O2(g) → H2O(l)
ΔH = -286 kj
Calculate ΔH for the reaction:
2 C(s) + H2(g) → C2H2(g)
D3) Given the following data:
ΔH = -427 kj
2 O3(g) → 3 O2(g)
ΔH = +495 kj
O2(g) → 2 O(g)
NO(g) + O3(g) → NO2(g) + O2(g) ΔH = -199 kj
Calculate ΔH for the reaction:
NO(g) + O(g) → NO2(g)
E3) The reusable booster rockets of the space
shuttle use a mixture of aluminum and
ammonium perchlorate as fuel.
3 Al(s) + 3 NH4ClO4(s) → Al2O3(s) + AlCl3(s) +
3 NO(g) + 6 H2O(g)
o
Calculate ∆H .