EST II – Individual Subject Test

Student’s Name _____________________________________

National ID _____________________________________
Test Center: _____________________________________

Subject: Chemistry
Duration: 60 minutes
85 Multiple Choice Questions

Instructions:
- Place your answer on the answer sheet. Mark only one answer for each of the multiple
choice questions.
- Avoid guessing. Your answers should reflect your overall understanding of the
subject matter.
- Calculator is not allowed.
- Periodic Table is available at the end of the booklet as a reference.
Note: For all questions involving solutions and/or chemical equations, assume that the system
is in pure water unless otherwise stated.

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Directions: Each set of lettered choices below refers to the numbered statements or questions
immediately following it. Select the one lettered choice that best fits each statement or answers
each question, and then fill in the corresponding oval on the answer sheet. A choice may be
used once, more than once, or not at all in each set.

Questions 1 – 9 Refer to the following compounds:

A. Carbon dioxide gas (CO2)
B. Ethanoic acid (CH3COOH)
C. Water (H2O)
D. Methane gas (CH4)
E. Acetone (CH3COCH3)
F. Sodium Chloride (NaCl)
1. The compound exhibiting the strongest intermolecular force.
2. A nonpolar organic compound.
3. A nonpolar inorganic compound.
4. Dipole-dipole intermolecular forces make the strongest force among this compound.
5. All the types of intermolecular forces are present in it.
6. Its molecular geometry is bent.
7. The molecule that exhibits the lowest intermolecular forces.
8. The molecule with a tetrahedral structure.
9. Molecules that are held together only by hydrogen bonding as intermolecular forces.

Questions 10 – 13 Refer to the units of:

A. Moles per liter
B. Grams per mole
C. Moles per kilogram
D. Degrees Celsius times kilogram per mole
10. Molar mass
11. Molality
12. Molarity
13. Molal boiling-point elevation constant

Questions 14 – 16:
A. H+ + OH → H2O
B. C + O2 → CO2
C. 2H2O2 → 2H2O + O2
14. A redox synthesis reaction
15. A disproportionation redox reaction
16. A non-redox reaction

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Questions 17 – 19 Refer to the following bar graph representing the percentage yield of three
reactions labelled as (A), (B), and (C) starting with the same mass of iron. The % yield differs
based on the surface area of iron in each chemical reaction:

A B C

17. Which reaction shows that the iron used is in the powdered form?
18. Which reaction shows that the iron used is a block?
19. Which reaction shows that the iron used is made from tiny pieces?

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Questions 20 – 22 Refer to the following curve representing the reaction rate of gas produced:

20. The reaction has stopped.

21. The reaction rate is the highest at this stage.
22. The reaction starts to slow down.

Questions 23 – 25: Use the following names to answer questions 23-24-25.

A. Zinc sulfite
B. Zinc sulfate
C. Zinc sulfide
23. Choose the correct name of ZnS compound.
24. Choose the correct name of ZnSO3 compound.
25. Choose the correct name of ZnSO4 compound.

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Directions: Each of the questions or incomplete statements below is followed by five suggested
answers or completions. Select the one that is best in each case and then fill in the corresponding oval
on the answer sheet.

26. What is the value of the angular quantum number (l) for the (d) sublevel?
A. 0
B. 1
C. 2
D. 3
E. None of the above

27. Once the electron in a hydrogen atom absorbs a quantum of energy, it:
A. Is now in its ground state.
B. Is now in its excited state.
C. Has released a photon.
D. Has released a proton.
E. Stays in its energy level.

28. Which element has the same s and p configurations for principal energy level 3 as the element
F has for its principal energy level 2?
A. Na
B. Al
C. P
D. Cl
E. S

29. If the electron configuration of an element is 1s22s22p63s23p5, the element is:

A. Iron
B. Bromine
C. Chlorine
D. Phosphorus
E. Iodine

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30. Given the following compounds where several common substances are listed in three separate
columns based on their behavior to conduct electricity. These columns are labeled as I, II, and
III.
I II III
HCl, HBr, HI CH3CO2H CH3OH (methanol)
HClO4 HF C2H5OH (ethanol)
HNO3 C12H22O11 (sucrose)
H2SO4

The right labels for columns I, II, and III are:

A. Weak electrolytes, nonelectrolytes, and strong electrolytes respectively
B. Weak electrolytes, strong electrolytes, and nonelectrolytes respectively
C. Strong electrolytes, nonelectrolytes, and weak electrolytes respectively
D. Strong electrolytes, weak electrolytes, and nonelectrolytes respectively
E. Nonelectrolytes, weak electrolytes, and strong electrolytes respectively

31. Given the following sets of molecular compounds:

I: CO2, H2CS, Br2, SF2
II: Br2, SF2, N2H4, H2
III: O2, CO2, H2CS, H2O

Which of the following sets contains single covalent bonds only?

A. I only
B. I and II
C. I and III
D. II only
E. None of the above

32. The correct charge for the most common monatomic ions for a nonmetal in Group 6A is:
A. 1
B. 2
C. 2+
D. 1+
E. 3

33. Which combination of atoms is most likely to produce a compound with ionic bonds?
A. Ca and F
B. P and H
C. S and Br
D. C and Cl
E. N and H

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34. With respect to calcium ions, chloride ions, and argon atoms, which of the following
statements is correct?
A. All the species have the same mass number.
B. All the species have the same number of neutrons.
C. All the species have the same number of protons.
D. All the species have the same number of nucleons.
E. All the species have the same number of electrons.

35. Which of the following violates the octet rule?

A. NF3
B. OF2
C. HF
D. PCl5
E. SiF4

36. Which statement is true?

A. Sodium chloride solution is a poor conductor of electricity.
B. Both sodium chloride and glucose are good conductors of electricity.
C. Sodium chloride solution is a good conductor of electricity.
D. Both sodium chloride solution and glucose are poor conductors of electricity.
E. Sodium chloride, in its solid state, is a good conductor of electricity.

37. Which of the following has the smallest radius?

A. Na
B. Br
C. P
D. Cl
E. K

38. The ability of an atom to attract electrons is best quantified by the:

A. Electronegativity
B. First ionization potential
C. Ionic ability
D. Both (A) and (B)
E. None of the above

39. Electronegativity __________ from left to right within a period and __________ from top to
bottom within a group.
A. decreases, increases
B. increases, increases
C. increases, decreases
D. stays the same, increases
E. increases, stays the same

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40. The correct order of the metallic character is:
A. B>N>C
B. F > Cl > S
C. Si > P > S
D. P > S > Se
E. Na > K > Rb

41. Which of the following phase changes is not endothermic?

A. Evaporation
B. Condensation
C. Sublimation
D. Melting
E. Boiling

42. Which of the following statements is true in liquids?

A. Particles at the surface evaporate the fastest whatever their kinetic energy is.
B. Particles far from the surface evaporate the fastest whatever the kinetic energy is.
C. Particles with the lowest kinetic energy evaporate the fastest.
D. Particles with the highest kinetic energy evaporate the fastest.
E. Both (B) and (D)

43. Which of the following does not involve a phase change?

A. Melting
B. Boiling
C. Diffusion
D. Evaporation
E. Freezing

44. A balloon is heated from room temperature to 58ºC. As a result, the gas inside the balloon
increases in volume. Which gas law explains this phenomenon?
A. Gay-Lussac’s Law
B. Boyle’s Law
C. Charles’ Law
D. Dalton’s Law
E. Combined Gas Law

45. A gas is confined to a steel tank with a fixed volume. At 293 K, the gas exerts a pressure of
8.53 atm. After heating the tank, the pressure of the gas increases to 10.4 atm. What is the
temperature of the heated gas?
A. 357 K
B. 326 K
C. 240 K
D. 926 K
E. 423 K

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 46. How many grams of Ca(OH)2 are contained in 1500 mL of 0.0250 M Ca(OH)2 solution?
A. 3.17 g
B. 2.78 g
C. 1.85 g
D. 2.34 g
E. 4.25 g

Questions 47 – 50 Refer to an experiment performed that is described by the figure below in three
consecutive steps:

Step 1 Step 2 Step 3

47. The following experiment describes:
A. Preparation of a solution starting from a solid solute
B. Diffusion process of iodine
C. Preparation of a solution starting from a commercial solution
D. Mixing two solids
E. Distillation process

48. The equipment used in this experiment are:

A. Erlenmeyer Flask, plastic wash bottle, and burette
B. Erlenmeyer Flask, plastic wash bottle, and volumetric flask
C. Volumetric Flask, plastic wash bottle, and burette
D. Volumetric Flask, plastic wash bottle, and volumetric pipette
E. Volumetric Flask, plastic wash bottle, and graduated pipette

49. In step 1:
A. A liquid is withdrawn with a volumetric pipette
B. A liquid is introduced into the flask
C. A liquid is measured by the graduated pipette
D. A liquid is measured by the volumetric burette
E. None of the above

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50. In step 3:
A. A concentrated solution is prepared
B. A dilute solution is prepared
C. A solution with moderate concentration is formed
D. Two solutions are prepared
E. A solvent is synthesized

51. What is the sum of the balancing coefficients for the following equation?
FeBr3 + H2SO4 → Fe2(SO4)3 + HBr
A. 11
B. 10
C. 12
D. 3
E. 6

52. The decomposition reaction of 0.42 mol of KClO3 takes place according to the following
chemical equation: 2KClO3(s) → 2KCl(s) + 3O2(g)
What is the reaction yield if 16 g of oxygen gas is produced?
A. 79.36 %
B. 42.22 %
C. 85.51 %
D. 75.24 %
E. 69.10 %

53. At STP, 0.2 mol of calcium oxide is best prepared from the reaction between:
A. 4.48 L of oxygen and excess calcium
B. 0.2 mol of calcium and 4.48 L of oxygen gas
C. 22.4 L of oxygen gas and excess calcium
D. 0.1 mol of calcium and excess oxygen
E. 2.24 L of oxygen gas and 0.2 mol of calcium

54. Given the following equation: 3Mg + 2H3PO4 → Mg3(PO4)2 + 3H2

How many liters of hydrogen gas at STP is liberated when of 2.4 g of magnesium reacts with
30 mL of 1.00 M H3PO4 solution?
A. 0.045 L
B. 2.016 L
C. 2.241 L
D. 10.801 g
E. 1.008 L

55. When an Arrhenius acid and a base react together, the result is:
A. Aqueous forms of the acids and bases
B. A salt and water
C. An insoluble covalent compound
D. A salt
E. None of the above

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 56. The oxidation number of chlorine in perchloric acid HClO4 is:
A. 7
B. +1
C. +7
D. 0
E. 1

Questions 57–60 Refer to the table given below:

Common Acid-Base Indicators

Approximate
Indicator pH range for Color change
color change
Methyl orange 3.2 - 4.4 Red to yellow
Bromothymol blue 6.0 - 7.6 Yellow to blue
Phenolphthalein 8.2 - 10 Colorless to pink
Litmus 5.5 - 8.2 Red to blue
Bromocresol green 3.8 - 5.4 Yellow to blue
Thymol blue 8.0 - 9.6 Yellow to blue

57. The proper indicator to be used in the titration reaction of a strong acid with a strong base is:
A. Methyl orange
B. Bromothymol blue
C. Phenolphthalein
D. Bromocresol green
E. Thymol blue

58. The color of the resulting solution obtained in item (57) at the equivalence point is:
A. Green
B. Red to yellow
C. Colorless
D. Pink
E. None of the above

59. What is the reading of the pH electrode at the equivalence point for the titration taking place
in item (57) at 25ºC?
A. 3
B. 6.8
C. 7
D. 10
E. 4

60. Thymol blue was used as an indicator to identify the equivalence point of an acid (A) with a
base (B); thus:
A. A is a strong acid and B is a weak base
B. Both A and B are weak
C. Both A and B are strong
D. A is a weak acid and B is a strong base
E. This indicator cannot identify the strength of A and B
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61. The % composition of each element in calcium carbonate is:
A. 40% Ca, 12% C, 16% O
B. 25% Ca, 15% C, 60% O
C. 57% Ca, 9% C, 34 % O
D. 26% Ca, 14% C, 60% O
E. 40% Ca, 12% C, 48% O

62. The freezing point of a solution is lowered by:

A. Increasing the kinetic energy
B. Decreasing the number of solute particles
C. Increasing the pressure on the solution
D. Increasing the number of solute particles
E. Increasing both solute and solvent particles

63. A colligative property of water is:

A. Solubility
B. Freezing point
C. Molecular structure
D. Boiling point
E. Both B and D

64. A reaction takes place between zinc metal and copper sulfate solution forming zinc sulfate.
Hence,
A. Zn is less reactive than copper
B. Sulfate is more reactive than Zinc
C. Zinc is more reactive than copper metal
D. Copper is more reactive than zinc metal
E. Copper is more reactive than zinc ions

65. What major reactant is reduced in a combustion reaction?

A. Carbon dioxide
B. Water
C. Water vapor
D. Oxygen gas
E. Hydrogen gas

66. The solubility product expression for tin (II) hydroxide, Sn(OH)2, is:
A. [Sn2+][OH]
B. [Sn2+]2[OH]
C. [Sn2+][OH]2
D. [Sn2+]3[OH]
E. [Sn2+][OH]3

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67. Assume that the molar concentration of iron (III) is represented by x and the molar
concentration of fluoride is represented by y. What is the solubility product constant
expression of iron (III) fluoride?
A. x3y
B. xy
C. x2y3
D. xy3
E. x3y3

68. The empirical formula of butene is CH2 and the molar mass of this compound is 56 g/mol. The
molecular formula of this compound is:
A. C3H4
B. C4H8
C. C2H2
D. C2H4
E. None of the above

69. Caffeine contains by mass composition 49.5% C, 5.15% H, 28.9% N and 16.5 % O and the
molecular mass is 195 g/mol. The empirical and molecular formula of caffeine are:
A. C8H10N4O and C4H5N2O respectively
B. C4H5N2O and C16H20N8O4 respectively
C. C8H10N4O and C4H5N2O2 respectively
D. C4H5N2O and C8H10N4O2 respectively
E. None of the above

70. How many moles of lithium are there in 1.204 × 1024 lithium atoms?
A. 1 mol
B. 1.999 mol
C. 7.248 × 1024 mol
D. 1.999 × 1024 mol
E. None of the above

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Questions 71–75 Refer to the following information present below:
Ethylene (C2H4) is a hydrocarbon that can undergo a complete combustion reaction.

71. The type(s) of bonding present in a molecule of ethylene is/are:

A. Single covalent bonds only
B. Single and double covalent bonds
C. Single and triple covalent bonds
D. Triple covalent bonds only
E. Both double and triple covalent bonds

72. The equation representing the complete combustion reaction of ethylene is:
A. C2H4 + 3O2  2CO2 + 2H2O
B. C2H4 + 2O2  2CO2 + 2H2O
C. C2H4 + 3O2  CO2 + 2H2O
D. C2H4 + 3O2  CO2 + H2O
E. C2H4 + 2O2  CO2 + 2H2O

73. 45 grams of ethylene (C2H4) reacts with excess oxygen, how many grams of carbon dioxide
are produced?
A. 114.4 g
B. 3.2 g
C. 141.4 g
D. 90.1 g
E. 3.7 g

74. What will be the mass of carbon dioxide if 45 g of ethylene reacts with 5 L of oxygen gas?
A. It will stay the same
B. It will increase
C. It will decrease
D. It will double
E. None of the above

75. If ethylene undergoes an incomplete reaction, then the products will be:
A. Carbon dioxide and water in the form of a liquid
B. Soot and water vapor
C. Carbon monoxide and water vapor
D. Carbon monoxide, soot, and water vapor
E. Either (B) or (C)

76. In what manner will the increase of pressure affect the following equation?
C(s) + H2O(g) ↔ CO(g) + H2(g)
A. Shift in the reverse direction
B. Shift in the forward direction
C. Increase in the yield of hydrogen
D. No effect
E. Increase in the amount of carbon monoxide

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77. If the reactants in a reversible reaction are doubled, the equilibrium constant:
A. Becomes double its amount
B. Becomes half its amount
C. Becomes one third of its amount
D. Become triple its amount
E. Remains the same

78. 2SO3(g) ↔ 2SO2(g) + O2(g)

The equilibrium constant expression (Kc) for the reaction above is:
A. [SO2]2/[SO3]
B. [SO2]2[O2]/[SO3]2
C. [SO3]2/[SO3]2[O2]
D. [SO2][O2]
E. None of the above

79. Upon melting, thermal energy is:

A. Liberated
B. Taken in
C. Not needed
D. Not changing
E. A variable component based on the identity of the molten substance

80. A chemist in a laboratory heats a substance from 10ºC to 25ºC; the thermal energy required is
30000 Joules. If the mass of this substance is 40 kg, the specific heat of this substance is:
A. 25 J.kg-1ºC-1
B. 50 J.kg-1ºC-1
C. 75 J.kg-1ºC-1
D. 100 J.kg-1ºC-1
E. 125 J.kg-1ºC-1

81. Given the following word equation:

bromine + potassium iodide → potassium bromide + iodine
The balancing coefficient and symbol of iodine produced are respectively:
A. 1, I1
B. 2, I2
C. 3, I2
D. 2, I1
E. 1, I2

82. Which of the following is the correct equation for the reaction that takes place when solid
phosphorus combines with oxygen gas to form diphosphorus pentoxide?
A. P(s) + O2(g) → PO2(g)
B. 2P(s) + 5O(g) → P2O5(s)
ହ
C. 2P(s) + O2(g) → P2O5(s)
ଶ
D. P2O5(s) → P2(s) + O2(g)
E. P2(s) + O5(g) → P2O5(s)

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83. The order of the following chemical elements He, Ne, Ar represents:
A. Increasing first ionization energy
B. Increasing electronegativity
C. Increasing atomic radius
D. Random and no order of any periodic trend
E. None of the above

84. The major starting material for the manufacturing of synthetic polymers as plastic is:
A. Methanol
B. Ethanol
C. Ethylene
D. Acetylene
E. Acetic acid

85. Given the following equation: NH3(aq) + H2O(l) → NH4+(aq) + OH(aq).

The conjugate acid and conjugate bases are respectively:
A. OH and NH4+
B. NH4+ and OH
C. NH3 and H2O
D. NH3 and OH
E. None of the above

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