1st Year Chemistry First half Book Paper

Q1. Multiple choice questions (Attempt all · 80 × 0.5 = 40)

1. Semi-conductors possess electrical conductivity:
   1. Equal to metals
   2. Higher than metals
   3. Equal to insulators
   4. Between conductors and insulators
2. The activation energy for a reaction can be:
   1. Increased by increasing temprature
   2. Increased by decreasing temprature
   3. Decreased by increasing concentration of reactants
   4. None of these
3. A reversible reaction is one in which:
   1. Reactants completely convert into products
   2. Products cannot react further
   3. Products react to form reactants again
   4. Reaction occurs only in one direction
4. The common ion effect occurs when:
   1. Two strong acids are mixed
   2. Two salts are decomposed
   3. Two bases are neutralized
   4. Two compounds produce the same ion in solution
5. What is correct statement about Al-Ghazali's approach? (i) He thought that every event must have a cause (ii) He thought that there is succession of events, not causation (iii) He thought that God can suspend the habitual continuation of events۔
   1. i & ii only
   2. ii & iii only
   3. iii only
   4. i,ii & iii
6. In a catalytic converter, NO reacts with CO to form:
   1. CO₂ + H₂O
   2. N₂ + CO₂
   3. NH₃ + CO
   4. NO₂ + C
7. Which type of bonding involves a "sea of delocalized electrons"?
   1. Covalent
   2. Ionic
   3. Metallic
   4. Hydrogen
8. Evaporation causes cooling because:
   1. Molecules absorb energy from surroundings
   2. Molecules release heat
   3. Vapour pressure decreases
   4. Surface area increases
9. Born Haber cycle is used to determine lattice energies of _______:
   1. Molecular solids
   2. Ionic solids
   3. Covalent solids
   4. Metallic solids
10. The reactant that is completely consumed during a reaction is called:
    1. Non-limiting reactant
    2. Excess reactant
    3. Limiting reactant
    4. Catalyst
11. As we go down Group 1, ionization energy:
    1. Increases
    2. Decreases
    3. Remains same
    4. Becomes irregular
12. The element magnesium belongs to which group based on successive ionization energies?
    1. Group 1
    2. Group 2
    3. Group 3
    4. Group 7
13. In a graph of concentration vs. time, the slope of the curve represents:
    1. Activation energy
    2. Rate of reaction
    3. Temperature
    4. Pressure
14. The oxidation of SO₂ to SO₃ is:
    1. Endothermic
    2. Exothermic
    3. Neutral
    4. Reversible only at high temperature
15. When air is bubbled through pure water, the pH is lowered from 7.0 to 5.6, which gas in the air is responsible for this change.
    1. Argon
    2. Carbon dioxide
    3. Nitrogen
    4. Oxygen
16. The Greek word "atomos" means:
    1. Divisible
    2. Smooth
    3. Breakable
    4. Indivisible
17. Sulphuric acid acts as a dehydrating agent because it:
    1. Contains water
    2. Removes water from compounds
    3. Forms crystals easily
    4. Produces oxygen
18. A greater difference in electronegativity between two atoms results in a bond that is:
    1. More covalent
    2. Nonpolar
    3. Less ionic
    4. More polar
19. Cleavage planes are a property of:
    1. Amorphous solids
    2. Gases
    3. Liquids
    4. Crystalline solids
20. The heat of neutralization between NaOH and HCl is approximately:
    1. +58.0 kJ/mol
    2. -58.0 kJ/mol
    3. +57.4 kJ/mol
    4. -57.4 kJ/mol
21. Which sample produces most hydrogen by reaction with excess of ?
    1. 0.25 mol Ca
    2. 0.25 mol Al
    3. 0.25 mol Zn
    4. 0.25 Na
22. The oxide of chlorine (Cl₂O₇) is:
    1. Basic
    2. Weakly acidic
    3. Strongly acidic
    4. Amphoteric
23. The region in space where the probability of finding an electron is maximum is called:
    1. Shell
    2. Orbital
    3. Subshell
    4. Energy level
24. The rate of reaction generally increases with:
    1. Increase in temperature
    2. Decrease in temperature
    3. Constant temperature
    4. Cooling
25. For the following reaction: 2A(g) ⇌ 3C(g) We can write:
    1. Kc > Kp
    2. Kc p
    3. Kp – Kc = 0
    4. Kp - Kc =-1
26. The formula for calculating pH is:
    1. pH = log [H⁺]
    2. pH = -log [OH⁻]
    3. pH = log [OH⁻]
    4. pH = -log [H⁺]
27. Al-Ghazali later rejected the idea of necessary causation because:
    1. It contradicted God's will
    2. It was unscientific
    3. It lacked experimental proof
    4. It was too simple
28. The bacteria responsible for nitrification are:
    1. Clostridium
    2. Azotobacter
    3. Pseudomonas
    4. Nitrosomonas
29. The difference in electronegativity greater than 1.8 indicates:
    1. Covalent bond
    2. Ionic bond
    3. Metallic bond
    4. Hydrogen bond
30. When gases are heated, their:
    1. Volume decreases
    2. Velocity of molecules increases
    3. Density increases
    4. Pressure decreases
31. Calorie is equivalent to:
    1. 4.18J
    2. 4.18KJ
    3. 0.418J
    4. 0.418KJ
32. How much volume of $NH_3$ gas produced when 3g$H_2$ react with excess of $N_2$ at STP.
    1. $24dm^3$
    2. $2.24dm^3$
    3. $2.4dm^3$
    4. $1.2dm^3$
33. The oxide of aluminum is:
    1. Strongly basic
    2. Amphoteric
    3. Acidic
    4. Strongly acidic
34. Atomic radius decreases across a period due to:
    1. Decrease in nuclear charge
    2. Increase in shielding
    3. Increase in number of shells
    4. Increase in nuclear charge
35. If the concentration of C changes from 0.0 to 0.38 mol dm⁻³ in 20 s, the rate of reaction is approximately:
    1. 0.38 mol dm⁻³ s⁻¹
    2. 0.45 mol dm⁻³ s⁻¹
    3. 0.20 mol dm⁻³ s⁻¹
    4. 0.019 mol dm⁻³ s⁻¹
36. The suitable temperature for maximum SO₃ yield in contact process is:
    1. 200-250°C
    2. 400-450°C
    3. 450-500°C
    4. 600°C
37. The pH range of phenolphthalein is:
    1. 46025
    2. 3.5-5.5
    3. 46244
    4. 46180
38. Al-Ghazali believed that nature follows:
    1. Specific principles set by God
    2. Random actions
    3. Automatic physical reactions
    4. None of these
39. Nitric acid is formed naturally when:
    1. Nitrogen combines with hydrogen
    2. Nitrogen dioxide dissolves in water
    3. Ammonia burns in air
    4. Ammonia reacts with HCl
40. The structure of SO₂ molecule is:
    1. Linear
    2. Trigonal planar
    3. Bent
    4. Octahedral
41. Which of the following shows hydrogen bonding?
    1. CH4
    2. H2S
    3. H2O
    4. CO2
42. Heat of _______ a substance is always negative:
    1. Formation
    2. Combustion
    3. Decomposition
    4. Solution
43. The SI unit of amount of substance is:
    1. Gram
    2. Mole
    3. Liter
    4. Atom
44. Which is correct for 12Mg?
    1. Period 1 element
    2. Group 1 element
    3. Period 2 element
    4. Alkaline earth metal
45. The magnetic quantum number for d-orbital has values from:
    1. -1 to +1
    2. -2 to +2
    3. -3 to +3
    4. -4 to +4
46. Activation energy is represented by the symbol:
    1. Ea
    2. ∆H
    3. Ep
    4. Et
47. Le Chatelier's principle states that when a system at equilibrium is disturbed, it:
    1. Stops reacting
    2. Shifts to reduce the effect of disturbance
    3. Increases temperature
    4. Changes into new compounds
48. An aqueous solution of which compound is basic.
    1. Ammonium nitrate
    2. Calcium chloride
    3. Ammonium acetate
    4. Potassium carbonate
49. According to Democritus, matter is made up of:
    1. Continuous material
    2. Chemical compounds
    3. Air and fire
    4. Uniform and indivisible particles
50. Sulphur dioxide is an important food preservative. Which leinte property makes sulphur dioxide useful in this role?
    1. It is a gas
    2. It is a reducing agent
    3. It reacts with oxygen to form sulphur trioxide
    4. It reacts with water to form an acidic solution
51. The shape of CO₃²⁻ ion is:
    1. Trigonal planar
    2. Linear
    3. Tetrahedral
    4. Trigonal pyramidal
52. Vapour pressure depends upon:
    1. Temperature
    2. Pressure
    3. Volume only
    4. Density
53. The energy required to break one mole of bonds to form neutral atoms is called:
    1. Bond energy
    2. Activation energy
    3. Ionization energy
    4. Lattice energy
54. When 1 mole of each of the following is completely burnt in oxygen, which will give the greater mass of $CO_2$?
    1. CO
    2. Diamond
    3. Ethane
    4. Methane
55. The vertical columns of elements in the periodic table are called:
    1. Rows
    2. Periods
    3. Groups
    4. Shells
56. Sodium has a characteristic:
    1. Blue emission line
    2. Red emission line
    3. Yellow emission line
    4. Green emission line
57. The rate equation Rate=k[CH₃Cl][Cl₂]½ represents:
    1. First order
    2. Second order
    3. Fractional order
    4. Third order
58. The equilibrium constant (Kc) is equal to:
    1. kr / kf
    2. kf / kr
    3. kf × kr
    4. 1 / (kf × kr)
59. Which of the following is an example of weak acid and strong base titration?
    1. HCl vs NaOH
    2. Oxalic acid vs NaOH
    3. H₂SO₄ vs KOH
    4. CH₃COOH vs NH₄OH
60. Al-Ghazali's famous book is:
    1. The Republic
    2. The Book of Knowledge
    3. The Story of Philosophy
    4. The Revival of Religious Science
61. Nitrogen is absorbed by the plants in the form of :
    1. Ammonium
    2. Nitrites
    3. Nitrates
    4. All
62. The molecular orbital of low energy is called:
    1. Bonding molecular orbital
    2. Antibonding orbital
    3. Non-bonding orbital
    4. Excited orbital
63. The intermediate phase lying between the solid phase and the normal liquid phase is called;
    1. Crystalline solid
    2. Liquid crystals
    3. Mesogens
    4. Crystal lattice
64. The standard enthalpy of combustion of carbon is:
    1. -285.8 kJ/mol
    2. -393.5 kJ/mol
    3. -571.6 kJ/mol
    4. -121 kJ/mol
65. The molarity (M) of a solution is defined as:
    1. Moles of solute × volume of solution
    2. Mass of solute / volume of solvent
    3. Volume of solute / dm³ of solvent
    4. Moles of solute / dm³ of solution
66. Elements adjacent to the blue leader line are called:
    1. Metals
    2. Non-metals
    3. Metalloids
    4. Noble gases
67. Intrinsic semiconductors are:
    1. Doped with impurities
    2. Pure materials like silicon or germanium
    3. Made of metals
    4. Made of insulators
68. In the expression A→B, the rate can be written as:
    1. dx/dt = -d[A]/dt = +d[B]/dt
    2. dx/dt = -d[B]/dt
    3. dx/dt = +d[A]/dt
    4. None of these
69. Macroscopic events are those which:
    1. Can be seen with naked eye
    2. Cannot be seen with naked eye
    3. Involve electrons only
    4. Are imaginary processes
70. If the pKa value of an acid is high, the acid is:
    1. Stronger
    2. Weaker
    3. Neutral
    4. Amphoteric
71. Al-Ghazali thought experiment was based on burning:
    1. Paper
    2. Cotton
    3. Wood
    4. Coal
72. The industrial manufacture of sulphuric acid is known as:
    1. Haber process
    2. Contact process
    3. Ostwald process
    4. Deacon process
73. Which chlorine compound has bonding that can be described as ionic with some covalent character?
    1. NaCl
    2. $MgCl_2$
    3. $AlCl_3$
    4. $SiCl_4$
74. According to kinetic molecular theory, water molecules have low kinetic energy because:
    1. They are far apart
    2. They have strong hydrogen bonding
    3. They are ionic
    4. They move very fast
75. The combustion of carbon to CO₂ evolves energy of:
    1. -110.52 kJ
    2. -282.98 kJ
    3. -393.5 kJ
    4. -571.6 kJ
76. The reactant that remains unreacted after the completion of reaction is called:
    1. Limiting reactant
    2. Solvent
    3. Catalyst
    4. Non-limiting
77. Magnesium reacts with chlorine to form:
    1. MgO
    2. MgCl₂
    3. Mg(OH)₂
    4. MgSO₄
78. A negative ion (anion) has:
    1. Deficit of electrons
    2. Equal electrons and protons
    3. Extra protons
    4. Excess of electrons
79. The rate equation for 2NO₂+F₂→2NO₂F is:
    1. Rate=k[NO₂]²
    2. Rate=k[F₂]
    3. Rate=k[NO₂][F₂]
    4. Rate=k[NO₂F]
80. An equilibrium system in which all reactants and products are in the same phase is called:
    1. Dynamic equilibrium
    2. Heterogeneous equilibrium
    3. Homogeneous equilibrium
    4. Static equilibrium