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Final Examinations in General Chemistry 2
For each statement or question, select the word or expression that, of
those given, best completes the statement or answers the question.
Record your answer on the separate answer sheet.
1. A reaction is endothermic if
A. heat energy is released during the
course of the reaction.
B. the value of the equilibrium constant
decreases with increasing
temperature.
C. the reaction proceeds more rapidly
at high temperature.
D. the energy of the product is greater
than that of the reaction.
2. Consider an exothermic reaction as summarized as
reactants→ products
There is an energy difference between the reactant and the product molecules. Which one
of the following best summarizes the main source of this energy difference between the
reactants and products?
A. kinetic energy is converted into
chemical bond energy
B. chemical bond energy is converted
into chemical bond energy
C. chemical bond energy is converted
into kinetic energy
D. kinetic energy is converted into
kinetic energy
3. When one mole of a certain compound is formed from its elements under standard
conditions, it absorbs 85 kilocalories of heat. A correct conclusion from this statement is
that the reaction has a
A. ∆Gfo equal to +85 kcal/mol
C. ∆Hfo equal to +85 kcal/mol
B. ∆Gfo equal to −85 kcal/mol
D. ∆Hfo equal to −85 kcal/mol
4. When a catalyst is added to a reaction at equilibrium, the rate of forward reaction
A. decreases and the rate of the
reverse reaction decreases
B. decreases and the rate of the
reverse reaction increases
C. increases and the rate of the
reverse reaction decreases
D. increases and the rate of the
reverse reaction increases
5. Equilibrium is reached in all reversible chemical reactions when the
A. forward reaction stops
B. reverse reaction stops
C. concentrations of the reactants and
the products becomes equal
D. rates of opposing reactions become
equal
6. In the reaction Zn + Cu2+ → Zn2+ + Cu, which species is oxidized?
A. Zn
C. Cu2+
B. Cu
D. Zn2+
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Prepared by MR. Henry N. Languisan
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Final Examinations in General Chemistry 2
7. In Metro Manila, brown coal deposits will be able to supply the city for years to come. On
Coal burning powers station,
A. all the chemical bond energy
released from coal is converted into
chemical use
B. all the heat energy released from
the coal is converted into electrical
energy
C. all the heat energy released from
the coal is converted into either
electrical or chemical bond energy
D. all the chemical bond energy
released from the coal is converted
into either electrical or heat energy
8. One kilojoule of heat
A. is sufficient to increase the
temperature of one gram of pure
water by 1 Kelvin
B. is produced when a current of
96,500 coulomb flows for one
second through a resistance
C. is produced when a current of one
ampere floes for 1000 second
through a resistance the ends which
differ in potential by one volt.
D. is needed to increase the
temperature of one gram of pure
water by 1 Kelvin
9. In the following reaction, what Cl2 undergoes
A. oxidation only
B. reduction only
C. both oxidation and reduction
D. neither oxidation nor reduction
10. As the number of effective collision between reacting particles increases, the rate of a
chemical reaction
A. disappears
B. decreases
C. increases
D. remains the same
11. What is the hydroxide ion concentration of a solution with a pH of 4
(Kw = [H3O+] [OH-] = 10-14) ?
A. 1 X 10-10 mole/liter
C. 1 X 10-4 mole/liter
B. 1 X 10-14 mole/liter
D. 1 X 10-7 mole/liter
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Prepared by MR. Henry N. Languisan
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Final Examinations in General Chemistry 2
12. Given the following potential energy diagram and the reaction A + B + 20 kcal→ C.
If the activation energy for the forward reaction is 60 kilocalories, then the activation energy
for the reverse reaction is
A. 30 kcal
B. 60 kcal
C. 40 kcal
D. 20 kcal
13. What is the reducing agent in the reaction?
C. Ag+
D. Ag
A. Pb
B. NO314. Given the reaction:
Which concentration relationship is an indication that this reaction has reached equilibrium?
A. [A] equals [B]
B. [C] equals [D]
C. [A] [B] [C] and [D] is constant
D. [A] [B] [C] and [D is equal
15. Given the equilibrium system at 298 Kelvin:
The equilibrium constant for the reaction Ka will change if there is an increase in
A. concentration of HCO3--(aq)
C. concentration of CO2(g)
B. temperature
D. pressure
16. Given the reaction:
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Prepared by MR. Henry N. Languisan
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Final Examinations in General Chemistry 2
When the equation is completely balanced using smallest whole numbers, the coefficient of
the H+ will be
A. 1
B. 3
C. 4
D. 2
Refer to the following information in answering 18 and 19.
150 cm3 of water at 303 Kelvin was placed in an insulated flask, and the temperature
measured at 20 second intervals for 3 minutes. The results are shown on the graph below.
After 60 seconds, 0.1 mol of the compound NaX was added to the water.
Room temperature was 293 Kelvin throughout the experiment.
17. The solution process NaX(s) +aq→ Na+(aq) + X-(aq) is
A. endothermic
B. thermoneutral
C. exothermic
D. endergonic
18. The sign of ΔH in the above reaction is
A. negative, as the system produces
heat which gradually loses to its
surroundingse
B. positive, as the water tends to gain
energy
C. negative, as the system gradually
gains heat from its surroundings
D. positive, as the solid tends to lose
energy to the water
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Prepared by MR. Henry N. Languisan
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Final Examinations in General Chemistry 2
Refer to the following information in answering the next question.
Given the Information
19. The enthalpy change when 1 mol of H2SO4 is formed according to the equation is given by
A. C
B. A
C. B
D. D
20. The equilibrium constant for the reaction is equal to
A.
B.
B
C
C.
D.
D
A
21. A mixture of SO2 and O2 at a fixed temperature reacts according to the equation
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Prepared by MR. Henry N. Languisan
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Final Examinations in General Chemistry 2
When equilibrium is established, which of the following ratios would be constant,
irrespective of the initial concentration of gases?
A.
C.
D.
B.
22. 1X1020 molecules of HI were introduced into a vessel of fixed volume at a particular
temperature. After some time there were 6.0 X 1019 molecules of HI, 2.0 X 1019 molecules
of I3 in the vessel. The temperature was unchanged and, at this temperature, the value of
the equilibrium constant for the reaction 2HI↔H2 + I2 is K = 2.0.
Which one of the following statements about the system is correct?
A. The system is not at equilibrium
B. It is impossible to decide whether
the system is at equilibrium or not,
as K refers to concentrations
expressed in mol dm -3 and the
volume of the vessel was not stated.
C. The system is at equilibrium
D. It is impossible to decide whether
the system is at equilibrium or not,
as the temperature was not stated
23. The addition of a catalyst to a system at equilibrium will increase the rate of
A. both forward and reverse reactions
B. neither the forward nor reverse
reaction
C. the reverse reaction only
D. the forward reaction only
24. Which type of reaction involves the transfer of electrons?
A. neutralization
B. alpha decay
C. oxidation-reduction
D. double replacement
25. The addition of a catalyst to a chemical reaction provides an alternate pathway that
A. decreases the activation energy
B. increases the potential energy of
reactants
C. decreases the potential energy of
reactants
D. increases the activation energy
26. The reaction of an Arrhenius acid with an Arrhenius base produces water and
A. a halocarbon
B. an ester
C. an aldehyde
D. a salt
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Prepared by MR. Henry N. Languisan
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Final Examinations in General Chemistry 2
27. A reaction reaches equilibrium at 100oC. The equation and graph representing this reaction
are shown below. N2O4(g) ↔ 2NO2(g).
The graph shows that the reaction is at equilibrium after 60. seconds because the
concentrations of both NO2(g) and N2O4(g) are
A. increasing
B. decreasing
C. constant
D. zero
28. During photosynthesis, plants use carbon dioxide, water, and light energy to produce
glucose, C6H12O6, and oxygen. The reaction for photosynthesis is represented by the
balanced equation below.
All of the following state evidence that indicates photosynthesis is an endothermic reaction.
hich of the following is not true
A. The energy term is on the right side
of equation.
B. ΔH is positive.
C. The reaction requires light.
D. Photosynthesis is an endothermic
reaction because light energy is
absorbed.
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Prepared by MR. Henry N. Languisan
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Final Examinations in General Chemistry 2
29. In a laboratory investigation, ammonium chloride was dissolved in water. Laboratory
procedures and corresponding observations made by a student during the investigation are
shown in the table below. The following state evidence from the investigation that indicates
the process of dissolving the NH4Cl(s) in water is endothermic except..
A. The dissolving of NH4Cl(s) is
endothermic because the
temperature of the solution is lower
than the temperature of the water.
B. The temperature decreased during
the dissolving.
C. No NH4Cl(s) observed after the
stirring.
D. The water temperature was 25.8°C
and the solution temperature was
11.2°C.
Base your answer from 30-32 from the following information.
Early scientists defined oxidation as a chemical reaction in which oxygen combined with
another element to produce an oxide of the element. An example of oxidation based on this
definition is the combustion of methane. This reaction is represented by the balanced
equation below.
Equation 1: CH4(g) + 2O2(g) → CO2(g) + 2H2O(g)
The definition of oxidation has since been expanded to include many reactions that do not
involve oxygen. An example of oxidation based on this expanded definition is the reaction
between magnesium ribbon and powdered sulfur when heated in a crucible. This reaction is
represented by the balanced equation below.
Equation 2: Mg(s) + S(s) → MgS(s)
30. All of which states why early scientists classified the reaction represented by equation 1 as
oxidation except
A. Oxides are formed.
B. A substance reacts with oxygen.
C. Hydroxides are fromed
D. both A and B
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Final Examinations in General Chemistry 2
31. Determine the change in oxidation number of carbon in equation 1
A. from -4 to +4
B. from zero to +4
C. from negative four to negative five
D. from -4 to zero
32. Write a balanced half-reaction equation for the oxidation that occurs in the reaction
represented by equation 2.
A. Mg → Mg2+ + 2eC. Mg + Mg2+ → 2eB. Mg + Mg3+ → 2eD. Mg2+ + Mg2+ +→ 2e33. Under the Brønsted concept of acids and bases, a base is:
A. a proton donor
B. a hydroxide donor
C. a proton acceptor
D. an electron pair donor
34. Which statement correctly describes an endothermic chemical reaction?
A. The products have higher potential
energy than the reactants, and the
ΔH is positive.
B. The products have higher potential
energy than the reactants, and the
ΔH is negative.
C. The products have higher potential
energy than the reactants, and the
ΔH is positive.
D. The products have lower potential
energy than the reactants, and the
ΔH is positive.
35. Which equation represents neutralization?
A.
B.
4
1
C.
D.
2
3
36. Given the balanced equation representing a reaction:
Ni(s) + 2HCl(aq) → NiCl2(aq) + H2(g)
In this reaction, each Ni atom
A. loses 2 electrons
B. gains 2 electrons
C. loses 1 electron
D. gains 1 electron
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Prepared by MR. Henry N. Languisan
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Final Examinations in General Chemistry 2
37. Some physical constants for ammonia are shown in the data table below.
Choose te correct numerical set-up and answer to the question.
A. q = mCΔT = (5..00 g)(4.71
J/g•K)(30. K) numerical set up,
71.0 J answer
B. q = mCΔT = (5.0.0 g)(4.7.1
J/g•K)(30. K) numerical set up,
.0710 J answer
C. q = mCΔT = (5.00 g)(4.71
J/g•K)(30. K) numerical set up, 710
J answer
D. q = mCΔT = (5.00 g)(0.4.71
J/g•K)(300. K) numerical set up,
710 J answer
38. The unbalanced equation below represents the decomposition of potassium chlorate
KClO3(s) → KCl(s) + O2(g)
Choose the letter of the correct balance equation in your answer booklet, using the
smallest whole-number
coefficients.
A. 3 KClO3(s) → 3 KCl(s) + 3 O2(g).
B. 3 KClO3(s) → 2 KCl(s) + 3 O2(g).
C. 2 KClO3(s) → 3 KCl(s) + 3 O2(g).
D. 2 KClO3(s) → 2 KCl(s) + 3 O2(g).
39. Determine the oxidation number of chlorine in the reactant. in item no 38
A. +3
B. +5
C. +4
D. +2
40. For the reaction
ΔH for
A. -220 kj/mol
B. -110 kj/mol
C. +55 kj/mol
D. -55 kj/mol
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Prepared by MR. Henry N. Languisan
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Final Examinations in General Chemistry 2
41. Given the following data, which of the following is the least endothermic
A.
B.
A
D
C.
D.
C
B
For the next three items, refer to he following information.
Oxygen gas and iron may react in three different ways as shown in the equation below,
42. Three equal amounts of iron are reacted with oxygen gas, as shown in the following
equation:
Which of the following is the most exothermic?
A.
B.
I
II
C.
D.
III
none
43. The ΔH for the following reaction, represented by the equation.
A.
C.
B.
D.
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Prepared by MR. Henry N. Languisan
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Final Examinations in General Chemistry 2
44. Carbon monoxide can act at a reductant as shown in the following equation
Carbon monoxide was used in the blast furnace for the production of iron from Fe2O3(s).
The energy change for the reaction of 1 mol of Fe2O3(s) with CO is
A.
C.
B.
D.
45. Equilibrium constant for each reaction changes as the
A. concentration of the reagents
increases
B. overall pressure increases
C. reaction proceeds
D. temperature increases
46. Consider the reactions represented by the following equation:
Which of the reaction is acids and bases?
A. (i and iii)
B. (i and ii)
C. (i, ii and iii)
D. (ii and iii)
47. In the above reaction, which of the following acts as a base?
A. HCN
C. CNB. H3O+
D. Zn
A series of reactions was carried out between acids and sodium salts. Each reaction
proceeded almost to completion. Equations for the reactions were:
48. Which of the following is the strongest acid?
A. HNO2
B. HCl2
C. HIO3
D. HOI
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Final Examinations in General Chemistry 2
49. Which of the bases is (are) stronger bases than NO2- ?
A.
B.
C
B
C.
D.
D
A
50. Given the lead-acid battery reaction::
Which electronic equation represents the half reaction for the oxidation that occurs?
A.
B.
3
1
C.
D.
2
4
51. Given the reaction at equilibrium:
N2(g) + 3H2(g) 2NH3(g) + 91.8 kJ
A. The rate of the forward reaction and
the
concentration of N2(g) both
decrease.
B. The rate of the forward reaction
decreases
and the concentration of N2(g)
increases.
C. The rate of the forward reaction and
the
concentration of N2(g) ) both
increase.
D. What occurs when the
concentration of H2(g) is
increased?
52. An investigation was conducted to study the effect of the concentration of a reactant on the
total time needed to complete a chemical reaction. Four trials of the same reaction were
performed. In each trial the initial concentration of the reactant was different. The time
needed for the chemical reaction to be completed was measured. The data for each of the
four trials are shown in the table below.
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Prepared by MR. Henry N. Languisan
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Final Examinations in General Chemistry 2
What is the effect of the concentration of the reactant on the rate of chemical reaction?
A. As concentration of the reactant
increases, the rate of the reaction
decreases.
B. As concentration of the reactant
decreases, the rate of the reaction
increases.
C. As concentration of the reactant
decreases, the rate of the reaction
decreases.
D. As concentration of the reactant
increases, the rate of the reaction
increases.
53. Given the diagram representing a closed system at constant temperature:
Which statement describes this system at equilibrium?
A. The mass of H2O(l) equals the
mass of H2O(g)
C. The rate of evaporation of H2O(l)
equals the rate of evaporation of
H2O(g)
D. The volume of H2O(l) equals the
volume of H2O(g)
B. The number of moles of H2O(l)
equals the number of moles of
H2O(g)
54. Which substance yields H+(aq) as the only positive ion in an aqueous solution?
A. CH3CHO
B. CH3COOH
C. CH3OCH3
D. CH3CH2OH
55. Given the balanced equation representing a reaction:
According to one acid-base theory, the H2O(l) molecules act as
A. a acid because they accept H+ ions
C. a base because they donate H+ ions
B. a acid because they donate H+ ions
D. a base because they accept H+ ions
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Prepared by MR. Henry N. Languisan
Ω
Final Examinations in General Chemistry 2
56. Which equation represents an oxidation-reduction reaction?
A.
B.
C.
D.
1
2
4
3
57. Which statement correctly describes a solution with a pH of 9?
A. It has a higher concentration of OHC. It has a higher concentration of
than H3O+ and causes methyl
H3O+ than OH- and causes methyl
orange to turn yellow
orange to turn yellow
B. It has a higher concentration of
D. It has a higher concentration of OHH3O+ than OH- and causes litmus
than H3O+ and causes litmus to
to turn blue.
turn blue.
58. Describe, in terms of LeChatelier’s principle, why an increase in temperature increases the
solubility of KNO3.
Given the equilibrium equation at 298 K:
A. Increasing the temperature favors
the forward, exothermic reaction.
B. Increasing the temperature favors
the backward, exothermic reaction.
C. Increasing the temperature favors
the forward, endothermic reaction.
D. Increasing the temperature favors
the backward, endothermic reaction.
Refer to the following in answering items 59-60.
In the smelting of iron ore, Fe2O3 is reduced in a blast furnace at high temperature by a
reaction with carbon monoxide. Crushed limestone, CaCO3, is also added to the mixture to
remove impurities in the ore. The carbon monoxide is formed by the oxidation of carbon
(coke), as shown in the reaction below:
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Prepared by MR. Henry N. Languisan
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Final Examinations in General Chemistry 2
59. Choose the balanced the equation for the reaction of Fe2O3 and CO , using the smallest
whole-number coefficients.
A. Fe2O3 + 3 CO → 2 Fe + 3 CO2
C. Fe2O3 + 3 CO → 3 Fe + 3 CO2
B. Fe2O3 + 4 CO → 2 Fe + 3 CO2
D. 2 Fe2O3 + 3 CO → 2 Fe + 3 CO2
60. What is the oxidation number of carbon in CaCO3?
A. +6
B. -6
C. -5
D. +4
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Prepared by MR. Henry N. Languisan