Catholic High Schools Chemistry Mock Exam for Grade

12
DATE: May 13-15, 2024 TIME ALLOWED:- 2:30hr
You may refer to the information given below when you work on some of the questions.
PHYSICAL CONSTANTS:
Gas constant, R = 8.314J/mol.K = 0.0821L.atm/mol.K Plank’s constant (h) = 6.626 x 10-34J/s
Speed of light, c = 3.0 x 108m/s Rydberg constant (RH) = 2.18 x 10-18J
ATOMIC NUMBER (Z) AND ATOMIC WEIGHT (A)
Element H He Li Be B C N O F Ne Na Mg Al Si P S Cl Ar K Ca Cu
Z 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 29
A 1 4 7 9 11 12 14 16 19 20 23 24 27 28 31 32 35.5 40 39 40 64

Direction: CHOOSE THE CORRECT ANSWER FROM THE GIVEN ALTERNATIVES AND BLACKEN
THE LETTER OF YOUR CHOICE ON THE SEPARATE ANSWER SHEET PROVIDED.
No calculator is allowed!

1. In the titration of a weak acid of unknown concentration with a standard solution of a strong base, a pH
meter was used to follow the progress of the titration. Which of the following is TRUE for this experiment?
A. The pH is less than 7 at the equivalence point.
B. The pH at the equivalence point depends on the indicator used.
C. The graph of pH versus volume of base added decreases gradually at first and then much more rapidly.
D. The [H+] at the half- equivalence point equals the ionization constant of the acid.
2. How many moles of NaOH should be contained in 250mL solution to neutralize completely 500mL of a
0.2M H2SO4 solution? 2NaOH + H2SO4 Na2SO4 + H2O
A. 0.01mol B. 0.05mol C. 0.03mol D. 0.20 mol
3. NH3 is a weak base Kb = 1.8 x 10-5, HCOOH is a weak acid, Ka = 1.8 x 10-4. A 0.1M solution of HCOONH4
would be
A. neutral B. weakly acidic C. weakly basic D. strongly basic
4. Identify the acid- base conjugate pairs in the reaction, HClO4 + H2SO4 ClO4 + H3SO4+
-

I. HClO4 and ClO4- III. H2SO4 and ClO4-

II. H2SO4 and H3SO4+ IV. HClO4 and H2SO4
A. I, only B. I and II, only C. I, II and IV only D. III and IV only
5. Identify the amphiprotic species among the following.
A. NH4+ B. OH- C. H2PO4- D. CO32-
6. Which of the following pairs CANNOT form a buffer system?
A. NaH2PO4 / Na2HPO4 C. HCOOH / HCOONa
B. NaHSO4 / H2SO4 D. KHCO3 / K2CO3
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7. An indicator with Kin value 2.4 x 10 is NOT suitable for which of the following titrations?
A. HCl against NaOH C. HI against Ba(OH)2
B. HF against RbOH D. HClO4 against NH3
8. The mass of H2SO4 needed to prepare 500mL of 3.00N H2SO4 solution is____.
A. 294g B. 147g C. 73.5g D. 36.75g

9. The pH of 0.1M solution of a weak base is 11.0. What is the value of the ionization constant for the base?
A. 10-11 B. 10-5 C. 10-3 D. 0.1

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10. During the electrolysis of an aqueous solution of CuSO4, what would happen to the mass of copper metal
deposited if the current is doubled and the electrolysis time is decrease to ¼ of its initial value?
A. It would stay the same C. It would increase to twice its initial value.
B. It would decrease to ¼ of its initial value D. It would decrease to ½ of its initial value
11. Given that, Cu + 2e  Cu (s) , E = +0.34V
2+ 0

Ni2+ + 2e  Ni (s) , E0 = - 0.28V.

Which of the following is TRUE about a galvanic cell represented by the equation:
Cu2+ (aq) + Ni(s)  Cu(s) + Ni2+(aq)
A. The reaction is spontaneous
B. Has Go > 0
C. = - 0.62V
D. The copper electrode is the anode half-cell
12. Which one is NOT true about the anode of an electrolytic cell?
A. It is connected to the positive side of a battery.
B. Anions migrate towards it and gain electrons.
C. Oxidation will take place on its surface.
D. Through the anode electrons will be transferred from the solution.
13. Two cells are connected in series. One contains FeCl3 and the other contains AgNO3 as the electrolyte. What
mass of Fe is deposited when 13.59gm of Ag is deposited? (At. wt: Ag = 108, Fe = 56)
A. 18.3gm B. 10.8gm C. 2.34gm D. 13.59gm
14. Consider the following half-reaction in a basic solution: Ag2O3AgO. The balanced half-reaction is
A. Ag2O3 + 4H+ + 4e- AgO + 2H2O C. Ag2O3 + H2O + 2e-  2AgO + 2OH-
B. Ag2O3 + 2H + 2e  2AgO + H2O
+ -
D. Ag2O3 + 2H2O + 4e- AgO + 4OH-
15. What is the cell potential of a galvanic cell given by the cell notation
Cr (s) | Cr3+ (0.01M) || Ag+ (0.10M) | Ag (s)? Eo (Ag+|Ag) = 0.77V and Eo (Cr3+| Cr) = -0.74V
A. 1.53V B. 1.49V C. 1.51V D. 1.50V
2+
16. The equilibrium constant for the reaction Sn(s) + 2Cu (aq) Sn (aq) + 2Cu+ (aq) at 25°C is
2+

approximately: [E0 (Cu2+/Cu+) = +0.15V and E0 (Sn2+/ Sn) = -0.14V]

A. 10-5 B. 105 C. 10-10 D. 1010
17. When an aqueous solution of AgNO3 is electrolyzed using platinum electrodes its concentration decreases
from 4M to 3M. If the same solution is electrolyzed using silver electrodes, then which of the following will
be observed?
A. The result will be the same. C. The decrease in concentration will be less.
B. The concentration of solution increases. D. No change in the concentration of the solution.
18. Which of the following is NOT true?
A. Vulcanized rubber is not recyclable.
B. Thermoset plastics are highly cross-linked polymers that form a three-dimensional network.
C. Addition polymers cannot be reshaped and reused on heating.
D. Butyl rubber is a copolymer of isobutylene and isoprene.
19. Which polymer is highly transparent and commonly used as glass substitute?
A. HDPE B. PVC C. PMMA D. PTFE
20. Styrene is a monomer, which usually polymerize by
A. addition polymerization. C. step-growth polymerization.
B. condensation polymerization. D. elimination of water molecules.
21. Which of the following raw materials is NOT put in the blast furnace when extracting iron from its ore?
A. Hematite B. Carbon monoxide C. Air D. Coke
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22. Polyester/ Dacron is:
A. a condensation polymer C. a copolymer of hexamethylene diamine and adipic acid
B. a polyamide D. a addition copolymer of phenol and formaldehyde
23. The Kraft process is used in:
A. making paper C. the production of cane sugar
B. tanning of skin D. making steel
24. Which of the following is NOT an ore of iron?
A. Siderite B. Hematite C. Chalcopyrite D. Magnetite
25. Industrially, nitric acid is manufactured by a process called ______________.
A. Solvay process B. Hall process C. Ostwald process D. Haber
process
26. Portland cement is mainly composed of:
A. limestone & silica C. calcium aluminate &calcium aluminate
B. limestone & clay D. slaked lime & silica
27. Which of the following elements is likely to be found free in nature?
A. Aluminum B. Phosphorus C. Sulfur D. Chlorine
28. Which of the following elements does NOT exhibit allotropy?
A. Oxygen B. Carbon C. Sulphur D. Nitrogen
29. Which of the following is NOT a raw material in the production of Pyrex glass?
A. B2O3 B. Na2CO3 C. SiO2 D. CaCO3
30. The products of the reaction below are________.
A. 1-butanol and methanol
+ LiAlH4 → B. methanol and 1-butanol
C. methanoic acid and1-butanol
D. methanol and butanoic acid

31. Carboxylic acids can be formed by the oxidative cleavage of ____.

A. alkenes B. ethers C. ketones D. secondary alcohols
32. Rancidity gives fats and oils unpleasant smell. Which of the following is NOT a possible cause of rancidity?
A. High degree of saturation.
B. The hydrolysis of ester linkage and oxidation across double bonds.
C. The raw material from which the fat/oil is synthesized.
D. High temperature and free air access.
33. Which of the following statements concerning esters is/are CORRECT?
i. The general formula of esters is RCOOR’.
ii. All esters are soluble in organic solvents.
iii. Lower members of esters are soluble in water.
A. i and ii only B. i and iii only C. ii and iii only D. i, ii and iii
34. Which of the following pieces of laboratory glassware should be used to most accurately measure out a
25.00 mL sample of a solution?
A. 25mL pipette C. 25mL Erlenmeyer flask
B. 25mL beaker D. 50mL graduated cylinder
35. A first-order reaction has a rate constant of 3.0  10 ─ 3 s ─ 1. The time required for the reaction to be 75%
complete is:
A. 95.8 s B. 201 s C. 231 s D. 462 s

36. In order to advance to the level of a theory, a hypothesis should be

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 A. obviously accepted by most people. C. a fully functional experiment.
B. in alignment with past theories. D. repeatedly confirmed by experimentation.

37. The rate law for the reaction: H2O2 + 2H+ + 2I ─  I2 + 2H2O is rate = k[H2O2][I ─ ].
Which of the following is a plausible mechanism for the reaction?

A. H2O2 + I ─  HOI + OH ─ slow C. H2O2 + I ─  HOI + OH ─ fast

OH ─ + H+ H2O fast OH + H  H2O
─ +
slow
HOI + H+ + I ─  I2 + H2O fast HOI + H+ + I ─  I2 + H2O fast

B. H2O2 + I ─  HOI + OH ─ fast D. H2O2 + I ─  HOI + OH ─ fast

OH + H  H2O
─ +
fast HOI + H+ + I ─  I2 + H2O fast
HOI + H+ + I ─  I2 + H2O slow OH ─ + H+ H2O slow
38. The following initial rate-concentration data was collected for the reaction
2X + Y + 2Z PRODUCT
Initial Concentrations, M Initial Rate, M/s
[X] [Y] [Z] ∆[PRODUCT] / ∆t
1.0 0.50 0.40 1.8 x 10-4
1.0 0.40 0.40 1.8 x 10-4
1.0 0.30 0.80 9.0 x 10-5
0.10 0.20 0.40 1.8 x 10-5
The rate law for this reaction is:
A. R = k[X]2[Y][Z]2 B. R = k[X][Z] C. R = k[X][Y]2[Z] D. R = k[X][Z]-1

39. A plot of lnK against 1/T (T in K) for a reaction is linear with a gradient of –1.20 × 104 K. The activation
energy, Ea, for the reaction is therefore _________.
A. 1.44 kJ mol–1 B. 99.8 J mol–1 C. 99.8 kJ mol–1 D. 693 J mol–1
40. Which of the following species has the least bond enthalpy?
A. N2 B. N2+ C. O2 D. C22-
41. Which statement is FALSE? A sigma molecular orbital:
A. May result from overlap of p atomic orbitals perpendicular to the molecular axis (side-on).
B. May result from overlap of p atomic orbitals along the molecular axis (head-on).
C. May result from overlap of two s atomic orbitals.
D. May result from overlap of one s and one p atomic orbitals.
42. What is the bond angle in phosphorus trichloride?
A. 1200 B. 109.50 C. 107.50 D. 900
43. Which of the following conversions involves change in both hybridization and shape?
A. NH3 → NH4+ B. H2O → H3O+ C.CH4 → C2H6 D. BF3 → BF4─

44. The kinds of orbitals that overlap to form the carbon-carbon bond in the molecule are:
H O
 ║ A. sp – sp C. sp3 – sp3
3 2
H  CH  C  H B. sp – sp D. sp2 - sp
45. The shape of the IO3─ ion is best described as
A. trigonal pyramidal B. trigonal planar C. T-shaped D. see-saw
46. Consider the following compounds:
Which types of isomers are they?
A. Position isomers C. Chain isomers
B. Functional isomers D. Geometrical
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47. Benzene does NOT change the color of Br2in CCl4 or that of KMnO4 solution; this is because benzene
A. resists addition C. oxidizes both Br2 and KMnO4
B. is an unsaturated hydrocarbon D. has a high carbon content
48. Which one is NOT isomeric with the others?
A. 1,3-btadiene B. 2-butyne C. 2-methyl propane D. Cyclobutene
49. Propene:
A. Reacts with HCl to give 1-chloro propane
B. Reacts with H2 in the presence of Ni catalyst to give C3H6
C. Reacts with water in the presence of acid catalyst to give a primary alcohol
D. Gives 1,2-propanediol when treated with alkaline KMnO2 solution
50. Which of the following compounds could NOT be oxidized to a carboxylic acid?
A. Propanal B. 1-Propanol C. Ethyl benzene D. 2-Methyl-2-propanol
51. Which of the following salts gives green color to a Bunsen flame?
A. LiI B. SrCl2 C. KI D. BaCl2
52. There are two beakers on a laboratory desk. One beaker contains 1.0 M HCl and the other contains tap
water. To distinguish the acid solution from the water, one would use _________ .
A. a piece of copper. C. phenolphthalein indicator
B. a piece of magnesium D. a piece of red litmus paper
53. Lemon juice has a hydronium ion concentration which is about 1000 times greater than that of pure water.
What is the approximate pH of the lemon juice?
A. 3.0 B. 4.0 C. 11.0 D. 1.0 x 10-11
54. A white precipitate is expected to be formed when an aqueous solution of sodium sulfate is added to an
aqueous solution of
A. iron(III) chloride C. magnesium chloride
B. potassium chloride D. barium chloride
55. The oxidation state of chlorine in NH4ClO4 is ______.
A. -1 B. +3 C. +5 D. +7
56. Which electrochemical cell is different?
A. Daniel cell B. NiCad cell C. Leclanche cell D. Alkaline cell
57. Given the reaction, Sn + 4HNO3Sn(NO3) + 2NO2 + 2H2O, which of the following is TRUE?
A. The oxidized substance is HNO3 C. Sn is the reducing agent
B. NO2 is the oxidizing agent D. Both the oxidizing and reducing agent is HNO3
58. Which of the following reactions does NOT involve oxidation-reduction?
A. CH4 + 3O2 2H2O + CO4 C. 2Na + 2H2O  2NaOH + H2
B. MnO2 + 4HCl  Cl2 + 2H2O + MnCl2 D. NaOH + H2S NaHS + H2O
59. What is the mass of hydrogen in 1.00g water?
A. 0.112g B. 0.888g C. 0.750g D. 0.10g
60. As atoms bond with each other, they
A. increase their potential energy, thus creating less stable arrangements of matter.
B. increase their potential energy, thus creating more stable arrangements of matter.
C. decrease their potential energy, thus creating less stable arrangements of matter.
D. decrease their potential energy, thus creating more stable arrangements of matter.

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61. What is the wavelength of light emitted when the electron in a hydrogen atom undergoes a transition from
energy level n = 4 to level n = 2?
A. 4.86 x 10-7/s B. 6.17 x 1014/s C. 1.62 x 10-15/s D. 1.9 x 1016/s

62. Which of the following diagrams represents the electron density in the dyz orbital?

B. C. D.
A.

63. Each atom in the periodic table has a unique set of spectral lines. Which one of the following statements is
the best explanation for this observation?
A. Each atom has a dense central nucleus.
B. Each atom has a unique set of energy levels.
C. The electrons in atoms are in constant motion.
D. Each atom is composed of positive and negative charges.
64. Which of the following atoms in the ground state has two half-filled orbitals?
A. P B. S C. Al D. Cl
65. The normal boiling point of the substance with the phase diagram
shown to the right is about _____°C.
A. 10 B. 20 C. 40 D. 50

66. The predominant intermolecular force in CH3 –NH-CH3 is ____.

A. London dispersion forces C. ion-dipole forces
B. dipole-dipole forces D. hydrogen bonding

67. The rate of diffusion of CH4 is ______ times that of O2?

A. B. C. 2 D.

68. If the absolute temperature of a gas is doubled and the pressure of the gas is halved, how will the volume
change?
A. It will increase by two times its original value. C. It will stay the same as its original value.
B. It will decrease to one fourth of its original value. D. It will increase by four times its original value.

69. 10HI + 2KMnO4 + 3H2SO4  5I2 + 2MnSO4 + K2SO4 + 8H2O

According to the balanced equation above, how many moles of HI would be necessary to produce 2.5 mol
of I2, starting with 4.0 mol of KMnO4 and 3.0 mol of H2SO4?
A. 2.5 B. 5.0 C. 8.0 D. 10.0
70. The following reaction is at equilibrium. CF2Br2 (g) CF2(g) + 2Br(g) ∆H = 424 kJ mol–1.
How will the system respond if the temperature is decreased?
A. The reaction will shift to the left. C. The rate of the reverse reaction will decrease.
B. The reaction will shift to the right. D. There will be no change to the equilibrium position.

71. A reaction between methane and hydrogen sulfide to produce carbon disulfide and hydrogen gas was
carried out. CH4 + 2H2S  CS2 + 4H2
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 32 g of methane produced 70.0 g of carbon disulfide. What was the percent yield for this reaction?
A. 22% B. 46% C. 59% D. 92%

72. The ratio of Kp / Kc for the reaction: CO(g) + ½ O2(g) CO2(g) is ______.
1/2
A. 1 B. RT C. RT D. RT-1/2
o
73. Kc for the reaction, A(g) + B(g) C(g) + D(g), is 20 at 25 C. If a container contains 1, 2, 4 and 5 moles
per liter of A(g), B(g),C(g), and D(g) respectively at 25oC, then the reaction will___.
A. proceed from left to right C. be at equilibrium
B. proceed from right to left D. be a net gain in reactant
74. In a photoelectric effect experiment, radiation of a metal with light frequency 2.00 x 10 18Hz yields electron
with maximum kinetic energy of 7.5 x 10-16J. Which one of the following is the value of V0?
A. 0.868 x 1018 m/s C. 2.00 x 1018 m/s
18
B. 86.8 x 10 m/s D. 868 x 1018 m/s
75. When water and carbon dioxide are formed during an exothermic reaction, it is probably a:
A. synthesis reaction C. combustion reaction
B. single displacement reaction D. double displacement reaction
76. A 30 L tank of oxygen is at 27 ºC with an internal pressure of 82 atm. How many moles of gas does the tank
contain?
A. 1111 mol B. 100 mol C. 2460 mol D. 1000 mol
77. In which of the following reactions will the equilibrium shift to the left when the pressure on the system is
increased?
A. C(s) + O2(g) CO2(g) C. 4NO2(g)+ 6H2O(g) 4NH3(g)+ 7O2(g)
B. 2Mg(s) + O2(g) 2MgO(s) D. 2H2(g) + O2(g) 2H2O(g)

78. Which of the following is NOT involved in the nitrogen cycle?

A. Rock B. Lightning C. Bacteria D. Man
79. What [H3O+] results when 25mL of 1.0M HCl is mixed with 10mL of 2.0M KOH?
A. 0.70 M B. 0.00 M C. 0.10 M D. 0.14 M
80. Which of the following is NOT true about the extraction of aluminum?
A. Na3AlF6 is added to lower the melting temperature of the Al2O3
B. As the reaction converts the electrode to CO2, the graphite anode must be replaced periodically
C. Molten Al2O3 is formed at the anode
D. Molten aluminum is formed at the cathode

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