What happens to the position of equilibrium, if a reversible exothermic reaction is subjected to a decrease in temperature?
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(B)
The position of equilibrium shifts to the right.
2
Which noble gas is radioactive and is produced as a decay product of uranium and thorium?
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(C)
Radon
3
Which of the following reactions would be expected to have the highest entropy change?
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(A)
Liquid → Gas
4
What is the sum of the oxidation numbers in a neutral compound?
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(C)
0
5
According to the kinetic theory of gases, the pressure exerted by a gas is due to
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(D)
The collisions of gas particles with the container walls
6
What is eutrophication?
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(B)
The excessive growth of algae due to nutrient enrichment
7
What is the name of the process by which ammonia is produced on an industrial scale?
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(D)
Haber process
8
Who proposed the planetary model of the atom with electrons orbiting the nucleus?
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(B)
Ernest Rutherford
9
Which of the following is an example of an endothermic reaction?
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(C)
Formation of table salt (NaCl) from sodium (Na) and chlorine (Cl\(_2\)).
10
What happens to the value of the equilibrium constant (Kc) for a reaction if the reaction is reversed?
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(D)
It becomes the reciprocal of the original value
11
What is the chemical structure of soap and detergent molecules?
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(A)
Hydrophilic head and hydrophobic tail
12
What is the solubility product constant (Ksp) used for?
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(B)
To determine the concentration of a solute in a saturated solution
13
Which trace gas in the atmosphere plays a significant role in the greenhouse effect?
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(C)
Carbon dioxide
14
Which of the following methods can be used to remove temporary hardness from water?
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(A)
Boiling
15
What is Faraday's constant?
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(D)
96,485 C/mol
16
A gas occupies a volume of 1.5 liters at a pressure of 2 atmospheres. If the pressure is increased to 4 atmospheres while the temperature remains constant, what will be the new volume of the gas?
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(C)
0.75 liters
17
Stainless steel is an alloy made up of
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(C)
Iron and chromium
18
What is the state of matter in which particles are widely spaced and move freely with high kinetic energy?
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(D)
Gas
19
Identify the reducing agent in the following reaction:
Zn + CuSO\(_4\) → ZnSO\(_4\) + Cu
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(B)
Zn
20
Balance the following redox reaction:
Fe\(_2\)O\(_3\) + CO → Fe + CO\(_2\)
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(D)
Fe\(_2\)O\(_3\) + 3CO → 2Fe + 3CO\(_2\)
21
What is the trend for ionization energy across a period in the periodic table?
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(A)
Increases from left to right.
22
Which type of chemical combination involves the transfer of electrons from one atom to another, resulting in the formation of oppositely charged ions?
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(A)
Ionic bonding
23
Which of the following alkanes has a straight-chain structure?
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(D)
Pentane (C5H12)
24
What is the product of the electrolysis of aqueous sodium chloride (NaCl) using inert electrodes?
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(B)
Hydrogen gas at the cathode and oxygen gas at the anode
25
When an acidic solution is diluted, what happens to its pH?
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(D)
It increases
26
Which of the following factors does NOT affect the rate of a chemical reaction?
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(C)
Molecular weight of products
27
Which organic compound is responsible for the characteristic aroma of fruits?
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(C)
Ester
28
What is the molar mass of water (H2O)?
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(A)
18 g/mol
29
What is the chemical formula of rust, which is formed on the surface of iron in the presence of oxygen and moisture?
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(D)
Fe\(_2\)O\(_3\)
30
How many pi (\(\pi\)) bonds are there in an alkene with six carbon atoms?
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(A)
1
31
What is the principal ore of iron, from which iron is extracted?
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(D)
Hematite
32
Which group does calcium belong to in the periodic table?
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(A)
Alkaline earth metals
33
Which of the following is a primary constituent of crude oil?
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(D)
Methane
34
What is the main source of carbon monoxide (CO) in urban areas?
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(B)
Vehicle emissions
35
What is the empirical formula of a compound containing 40.00% carbon, 6.67% hydrogen, and 53.33% oxygen by mass?
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(B)
CH\(_2\)O
36
Which separation technique is used to separate different pigments in a mixture based on their affinity for a stationary phase and a mobile phase?
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(A)
Chromatography
37
What is the common name for ethanoic acid?
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(A)
Acetic acid
38
What type of reaction is involved in the formation of alkanols from alkenes?
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(D)
Addition reaction
39
What is the mass percentage of carbon (C) in methane (CH4)? (The molar mass of carbon is approximately 12 g/mol.)
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(C)
75%
40
Which of the following is a common property of non-metals?
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(B)
Tend to gain electrons in chemical reactions
41
What is the symbol used to represent an alpha particle?
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(A)
α
42
When a substance is oxidized, it
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(A)
Loses electrons
43
A blue litmus paper turns red when dipped into a solution. What does this indicate about the solution?
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(C)
The solution is acidic
44
Which of the following compounds is an example of an electrovalent bond?
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(A)
NaCl (sodium chloride)
45
If gas A has a molar mass of 32 g/mol and gas B has a molar mass of 64 g/mol, what is the ratio of their diffusion rates?
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(A)
2:1
46
The contact process is used for the industrial production of
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(A)
sulfuric acid (H2SO4)
47
Which of the following is a unique property of water compared to other liquids?
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(C)
It expands when freezing
48
Sodium reacts vigorously with water to produce
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(C)
Sodium hydroxide (NaOH) and hydrogen gas (H2)
49
At room temperature and standard pressure, chlorine gas is in which state of matter?
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(D)
Gas
50
What is the molecular geometry of a molecule with three bonding pairs and no lone pairs around the central atom?
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(B)
Trigonal planar
51
Isotopes of an element have
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(A)
The same number of protons but different numbers of neutrons.
52
Which element is placed at the top of the electrochemical series?
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(C)
Sodium
53
Which transition metal is known for its multiple colorful oxidation states and compounds used in pigments and paints?
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(B)
Copper (Cu)
54
Which of the following methods is commonly used to remove suspended impurities from water?
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(C)
Filtration
55
What is the valency of an element with the electronic configuration 2, 8, 7?
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(B)
1
56
When anhydrous cobalt chloride paper is exposed to water, what color change is observed?
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(D)
From blue to pink
57
Which type of salt is found in antacid medications and is used to relieve heartburn and indigestion?
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(B)
Magnesium chloride
58
What is the atomic number of aluminium?
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(A)
13
59
Which of the following metals is commonly alloyed with copper to make brass?
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(D)
Zinc
60
What happens when alkanoic acids react with alcohols in the presence of an acid catalyst?
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(B)
Esterification
61
Which functional group is present in alkanals?
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(A)
Carbonyl group (C=O)
62
At 2.0 atm pressure, the volume of a gas is 4.0 L. If the pressure is reduced to 1.0 atm while keeping the temperature constant, what will be the new volume of the gas?
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(C)
8.0 L
63
What is the main environmental concern associated with sulfur dioxide emissions?
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(A)
Formation of acid rain
64
Benzene can be converted to its derivative toluene by the addition of a methyl group. The reaction is an example of
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(C)
Electrophilic substitution
65
Why is water often referred to as the "universal solvent"?
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(D)
Water can dissolve a wide variety of substances due to its polar nature
66
Which of the following mixtures is an example of a colloid?
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(A)
Milk
67
Which of the following substances is NOT hygroscopic?
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(D)
Aluminum
68
What is the mass (in grams) of 500 mL of ethanol? (density of ethanol = 0.789 g/mL)
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(C)
394.5 g
69
The heat of reaction can be determined experimentally using a device called a
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(A)
Calorimeter
70
Which halogen is a gas at room temperature and is pale yellow in color?
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(B)
Fluorine (F)
71
What unit of temperature should be used when applying the ideal gas law?
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(B)
Kelvin (K)
72
Chlorine gas is commonly used in the production of which of the following industrial compounds?
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(A)
Chlorofluorocarbons (CFCs)
73
The process of rusting is an example of the formation of
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(A)
Basic oxide
74
Which of the following is an example of a primary cell?
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(A)
Alkaline battery
75
Which of the following is a characteristic property of acids?
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(D)
React with metals to produce hydrogen gas
76
The lanthanides and actinides are located in which block of the periodic table?
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(C)
F-block
77
What is the IUPAC name for the compound CCl\(_4\)?
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(B)
Tetrachloromethane
78
Which of the following statements is true regarding the melting and boiling points of pure substances?
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(D)
The melting and boiling points can vary depending on the substance
79
An element has an atomic number of 8 and a mass number of 16. How many neutrons does this element have?
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(C)
8
80
Which of the following statements is true for strong electrolytes?
