Multiple Choice (KU) 1 mark each
Identify the choice that best completes the statement or answers the question.
____
1. Which of the following is an example of a polar molecule?
a. HCl
b. CO2
c. CH4
d. N2
____
5. Magnesium has an electronegativity value of 1.3, and oxygen has an electronegativity value of 3.4. When
magnesium and oxygen bond, which type of bond forms?
a. ionic bond
b. non-polar covalent bond
c. polar covalent bond
d. none of the above
____
9. Distilled water is added to a flask containing a certain volume of a potassium bromate, KBrO3(aq) solution.
Which of the following statements best describes the change in concentration of the solution that occurs as the
water is being added?
a. The concentration decreases because the number of moles of potassium bromate
decreases.
b. The concentration increases because the number of moles of potassium bromate increases.
c. The concentration decreases because the volume of solution increases.
d. The concentration increases because the volume of the solution increases.
____ 10. When a Bunsen burner is lit, the following reaction occurs: CH4(g) + 2 O2(g)
CO2(g)
+ 2 H2O(g). When plenty of oxygen is available, the complete combustion of methane results and the Bunsen
burner burns with a clean blue flame. Which of the following substances is the limiting reagent when a
Bunsen burner burns with a clean blue flame?
a. carbon dioxide, CO2
b. oxygen, O2
c. water, H2O
d. methane, CH4
____ 11. Which of the following is the molecular formula for a compound with empirical formula C2H5 and molar
mass 58.12 g/mol? The molar mass of carbon is 12.01 g/mol, and the molar mass of hydrogen is 1.01 g/mol.
a. C8H20
b. C6H15
c. C2H5
d. C4H10
____ 12. Hydrogen peroxide (H2O2) will decompose into water (H2O)and oxygen gas (O2). What mass of hydrogen
peroxide is required to produce 72.5 g of water? The molar mass of hydrogen peroxide is 34.0147 g/mol, and
the molar mass of water is 18.0153 g/mol.
a. 2.73 x 102 g
b. 38.4 g
c. 1.37 x 102 g
d. 0.112 g
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____ 13. What volume of a 2.00 mol/L hydrochloric acid solution is required to produce 250.0 mL of a 1.00 mol/L
solution?
a. 125 mL
b. 8.00 L
c. 500 mL
d. 1.25 L
____ 14. 31.5 g of magnesium hydroxide, Mg(OH)2, is dissolved to prepare 250.0 mL of solution. What is the amount
concentration of hydroxide ions in the solution? The molar mass of magnesium hydroxide is 58.3198 g/mol.
a. 0.540 mol/L
b. 1.08 mol/L
c. 4.32 mol/L
d. 2.16 mol/L
____ 15. Atoms of element X, having two valence electrons, combine with atoms of the element Y, having seven
valence electrons. Which of the following statements is true?
a. X 2 - ions are formed
b. Y 2 - ions are formed
c. the compound formed has the formula X2Y
d. the compound formed has the formula XY2
____ 17. If magnesium chloride is mixed with barium nitrate solution, what will precipitate?
a. magnesium nitrate
b. magnesium chloride
c. barium chloride
d. barium nitrate
e. nothing
____ 18. DDT is a common pesticide. The molecular formula for DDT is C14H9Cl5 (M = 354.48 g/mol). What is the
number of molecules in 10.0 g of DDT.?
a. 6.02 𝑥 1023 𝑚𝑜𝑙𝑒𝑐𝑢𝑙𝑒𝑠
b. 6.02 𝑥 1024 𝑚𝑜𝑙𝑒𝑐𝑢𝑙𝑒𝑠
c. 𝟏. 𝟕𝟎 𝒙 𝟏𝟎𝟐𝟐 𝒎𝒐𝒍𝒆𝒄𝒖𝒍𝒆𝒔
d. 2.13 𝑥 1026 𝑚𝑜𝑙𝑒𝑐𝑢𝑙𝑒𝑠
e. none of the above
True/False (KU) 1 mark each
Indicate whether the statement is true or false.
__T__ 1. The ability of one substance to dissolve into another substance depends on the polarity of the two substances.
__F__ 3. The molar mass of a compound is the product of the molar mass of each entity in the compound.
__T__ 4. A mole ratio is the predicted amount of a reactant, relative to another reactant, that will react according to the
balanced chemical equation.
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Short Answer
1. (TI) 3 marks
In an experiment, strips of the metallic elements X,Y, and Z were placed in metal nitrate solutions. The given
table summarizes the results of the experiment.
X(s)
Y(s)
Z(s)
XNO3(aq)
nr
r
r
YNO3(aq)
nr
nr
nr
ZNO3(aq)
nr
r
nr
Legend: r = single displacement reaction occurred
nr = no reaction occurred
Based on the results of the experiment, rank the metals X, Y, and Z in an activity series. (Most
reactive to least reactive)
The results table above was incorrect, and therefore it was impossible to answer. See corrections.
Corrected answer:
Y is most reactive
Then Z
And least reactive is X
2. (TI) 3 marks
Draw the Lewis structure for ClO3−.
3. (TI) 4 marks
Aqueous iron (III) nitrate is combined with aqueous sodium hydroxide.
a) Predict the products in the reaction and write the balanced chemical equation.
Fe(NO3)3(aq) + 3NaOH(aq)  3NaNO3(aq) + Fe(OH)3(s)
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b) Write the total ionic equation for this reaction.
Fe3+(aq) + 3NO3-(aq) + 3Na+(aq) + 3OH-(aq)  3Na+(aq) + 3NO3-(aq) + Fe(OH)3(s)
c) Write the net ionic equation for this reaction.
Fe3+(aq) + 3OH-(aq)  Fe(OH)3(s)
4. (TI) 4 marks
A 750.0 mL gas sample at 322 kPa and 25 C was compressed to 500.0 mL at a temperature of 30 C.
Calculate the final pressure.
491 kPa
5. (TI) 3 marks
a) If 50 grams of NH4Cl is dissolved at 50°C, how many additional grams of NH4Cl would be needed to
make the solution saturated at 80°C?
15g
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b) At what temperature do potassium chlorate and potassium chloride have the same solubility in water?
~95oC
c) Which compound is least soluble in water at 12°C?
KClO3
6. (A) 3 marks
A 10 mL sample of KI solution was analyzed by adding an excess of AgNO3 solution. The AgI that was
produced by the reaction had a mass of 2.29g. What was the amount concentration of KI?
KI + AgNO3  AgI + KNO3
M = 166.0g/mol 169.87g/mol 234.77g/mol
1.3 M
7. (TI) 4 marks
What is the volume of 72.5 g of chlorine gas, Cl2(g), at 104 kPa and 12.0 C?
22.9L
8. (A) 7 marks
If 1.50 L of 0.780 mol/L sodium sulfide, Na2S (M=78.07g/mol), is mixed with 1.00 L of a 3.31 mol/L lead(II)
nitrate, Pb(NO3)2 (M=331.22 g/mol), solution, would you expect a precipitate to form?
a) If so, write a balanced chemical equation for the reaction and identify the precipitate.
Na2S(aq) + Pb(NO3)2(aq)  PbS(s) + 2NaNO3(aq)
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b) What mass of precipitate would you expect to form if one forms?
280g
9. (C) 2 marks
Give IUPAC name for each of the following.
CCl4
____Carbon tetrachloride__________________________
SnI4
_____tin (IV) oxide_________________________
10. (C) 2 marks
Give the formulae for the following.
potassium bromide _____KBr_________________________
ammonium sulphide _______(NH4)2S______________________
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11. (A) 6 marks
Methylbenzene (toluene), C6H5CH3 (l), is a common paint thinner. It can be prepared by the following:
CH3Cl (g) + C6H6 (l)  C6H5CH3 (l) + HCl (g)
M= 50.49g/mol 78.12 g/mol 92.15 g/mol
36.46 g/mol
In an investigation, 25.0 g of benzene, C6H6, is combined with 20.0 g of chlormethane, CH3Cl, in the presence
of a catalyst.
a) Calculate the theoretical yield of toluene.
29.5g
b) If 22.0 g of C6H5CH3 is actually obtained, what is the percentage yield?
74.6%
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14. (C) 2 marks
In an experiment, a student held one metal spoon over an orange-coloured Bunsen burner flame and another
spoon over a blue-coloured Bunsen burner flame. After a few minutes, the spoon over the orange flame
became coated with a black substance, while the other spoon remained clean.
What type of combustion caused one spoon to be covered with a black substance and the other spoon to
remain clean?
Orange flame = incomplete combustion (soot)
Blue flame = complete combustion
15. (TI,A,C) 3 marks
An engineer is designing a new tank to hold hydrogen gas for use in an experimental vehicle’s fuel system.
The tank is to be made out of a special metal alloy that is much less dense than steel. The engineer needs to
know whether or not the alloy will be strong enough to hold a sufficient quantity of hydrogen under pressure.
The specifications call for 1.20 X 103 L of hydrogen at normal atmospheric pressure, 101 kPa to be
compressed into a 40.0 L tank made of the light alloy. The alloy can readily withstand pressures up to 5050
kPa.
a) Assuming constant temperature, calculate the pressure that will exist in a filled tank.
3030kPa
b) Predict whether the alloy will be able to hold the hydrogen safely.
YES
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