1st Year Chemistry Board Pattern Paper 2026

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

1. The reactant that is completely consumed during a reaction is called:
   1. Non-limiting reactant
   2. Excess reactant
   3. Limiting reactant
   4. Catalyst
2. Semi-conductors possess electrical conductivity:
   1. Equal to metals
   2. Higher than metals
   3. Equal to insulators
   4. Between conductors and insulators
3. Born Haber cycle is used to determine lattice energies of _______:
   1. Molecular solids
   2. Ionic solids
   3. Covalent solids
   4. Metallic solids
4. What is the main effect of crude oil leakage on the surface of water bodies?
   1. It increases light penetration
   2. It promotes aeration and plant growth
   3. It forms a black layer, blocking air and light from entering the water
   4. It adds essential nutrients for fish
5. 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
6. Which halogen has greenish yellow colour?
   1. $F_2$
   2. $Cl_2$
   3. $Br_2$
   4. $I_2$
7. Evaporation causes cooling because:
   1. Molecules absorb energy from surroundings
   2. Molecules release heat
   3. Vapour pressure decreases
   4. Surface area increases
8. The function of Al₂O₃ or concentrated H₂SO₄ is to:
   1. Oxidize alcohols
   2. Form esters
   3. Add hydrogen to double bonds
   4. Remove water from a molecule
9. Which type of bonding involves a "sea of delocalized electrons"?
   1. Covalent
   2. Ionic
   3. Metallic
   4. Hydrogen
10. 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
11. Catalyst used in catalytic cracking is generally:
    1. Iron oxide
    2. Nickel
    3. Zeolites
    4. Manganese dioxide
12. Basic hydrolysis of an ester produces:
    1. Carboxylic acid and alcohol
    2. Acid and ketone
    3. Aldehyde and water
    4. Carboxylate salt and alcohol
13. Which of the following gases is not a greenhouse gas?
    1. Carbon dioxide (CO₂)
    2. Methane (CH₄)
    3. Nitrogen (N₂)
    4. Nitrous oxide (N₂O)
14. 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
15. 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
16. Hydrolysis involves the attack of:
    1. Water molecule
    2. Acid molecule
    3. Oxygen molecule
    4. Hydrogen molecule
17. In a catalytic converter, NO reacts with CO to form:
    1. CO₂ + H₂O
    2. N₂ + CO₂
    3. NH₃ + CO
    4. NO₂ + C
18. Which test produces a silver mirror when reacted with an aldehyde?
    1. Fehling's test
    2. Benedict's test
    3. Tollen's test
    4. Iodoform test
19. The compound 2-methyl-2-chloropropane (t-butyl chloride) is a:
    1. Primary alkyl halide
    2. Secondary alkyl halide
    3. Tertiary alkyl halide
    4. Quaternary halide
20. As we go down Group 1, ionization energy:
    1. Increases
    2. Decreases
    3. Remains same
    4. Becomes irregular
21. In conjugated alkenes, the carbon atoms are:
    1. sp hybridized
    2. Unhybridized
    3. sp³ hybridized
    4. sp² hybridized
22. Amines are derivatives of:
    1. Water
    2. Ammonia
    3. Alcohol
    4. Ether
23. 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
24. The element magnesium belongs to which group based on successive ionization energies?
    1. Group 1
    2. Group 2
    3. Group 3
    4. Group 7
25. 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
26. Water is called a universal solvent mainly because of its:
    1. Low density
    2. Polarity and hydrogen bonding
    3. High temperature
    4. Lack of solubility
27. The oxidation of SO₂ to SO₃ is:
    1. Endothermic
    2. Exothermic
    3. Neutral
    4. Reversible only at high temperature
28. The thermal stability of hydrogen halides decreases in the order:
    1. HI > HBr > HCl > HF
    2. HF > HCl > HBr > HI
    3. HCl > HF > HBr > HI
    4. HI > HCl > HBr > HF
29. Cleavage planes are a property of:
    1. Amorphous solids
    2. Gases
    3. Liquids
    4. Crystalline solids
30. Retrosynthesis is the process of:
    1. Combining simple reactions to make a compound
    2. Distilling alcohols
    3. Separating organic mixtures
    4. Breaking a target compound into simpler precursors
31. 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
32. 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
33. J/L is the unit of :
    1. Energy density
    2. Specific energy density
    3. Energy
    4. Density
34. Which reagent is used to convert alcohol into bromoalkane?
    1. KBr + H₂SO₄
    2. KMnO₄
    3. SOCl₂
    4. NaBr
35. The process by which greenhouse gases trap heat in Earth's atmosphere is called:
    1. Global cooling
    2. Greenhouse effect
    3. Ozone depletion
    4. Solar reflection
36. In a graph of concentration vs. time, the slope of the curve represents:
    1. Activation energy
    2. Rate of reaction
    3. Temperature
    4. Pressure
37. The Greek word "atomos" means:
    1. Divisible
    2. Smooth
    3. Breakable
    4. Indivisible
38. The IUPAC name of HCOOH is:
    1. Butanoic acid
    2. Ethanoic acid
    3. Propanoic acid
    4. Methanoic acid
39. Sulphuric acid acts as a dehydrating agent because it:
    1. Contains water
    2. Removes water from compounds
    3. Forms crystals easily
    4. Produces oxygen
40. A carboxylic acid contains functional group :
    1. A Hydroxyl group
    2. A Carboxyl group
    3. Hydroxyl and Carboxyl group
    4. A Carboxyl and aldehyde group
41. In halogenoalkanes, a hydrogen atom of alkane is replaced by:
    1. Oxygen
    2. Nitrogen
    3. Halogen
    4. Sulphur
42. The oxide of chlorine (Cl₂O₇) is:
    1. Basic
    2. Weakly acidic
    3. Strongly acidic
    4. Amphoteric
43. Alkanes are also called:
    1. Aromatics
    2. Acetylenes
    3. Olefins
    4. Paraffins
44. Catalytic reduction of nitriles uses:
    1. H₂ / Ni
    2. H₂ / Cu
    3. H₂ / Fe
    4. H₂ / MnO₂
45. 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. $1.2dm^3$
46. The region in space where the probability of finding an electron is maximum is called:
    1. Shell
    2. Orbital
    3. Subshell
    4. Energy level
47. Calorie is equivalent to:
    1. 4.18J
    2. 4.18KJ
    3. 0.418J
    4. 0.418KJ
48. Which step involves cooperation among countries for sustainable water use?
    1. Water recycling
    2. Desalination
    3. Smart use of water
    4. International cooperation
49. 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
50. When NaCl reacts with concentrated H₂SO₄, the gas evolved is:
    1. HF
    2. HCl
    3. HBr
    4. HI
51. When gases are heated, their:
    1. Volume decreases
    2. Velocity of molecules increases
    3. Density increases
    4. Pressure decreases
52. Retrosynthesis works in which direction?
    1. Forward direction
    2. Backward from target to precursor
    3. Random reaction sequence
    4. Simultaneous pathway
53. The difference in electronegativity greater than 1.8 indicates:
    1. Covalent bond
    2. Ionic bond
    3. Metallic bond
    4. Hydrogen bond
54. The formula for calculating pH is:
    1. pH = log [H⁺]
    2. pH = -log [OH⁻]
    3. pH = log [OH⁻]
    4. pH = -log [H⁺]
55. Photovoltaic cells generate which type of current?
    1. Alternating current
    2. Direct current
    3. Pulsed current
    4. Magnetic current
56. In the oxidation of alcohols, the color of dichromate changes from:
    1. Blue to green
    2. Orange to green
    3. Green to brown
    4. Yellow to orange
57. Which of the following is a short-term effect of air pollution on human health?
    1. Increased cancer risk
    2. Respiratory problems
    3. Long-term memory loss
    4. None of the above
58. The rate of reaction generally increases with:
    1. Increase in temperature
    2. Decrease in temperature
    3. Constant temperature
    4. Cooling
59. 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
60. CH₃-CH₂-COCl is known as:
    1. Propanoyl chloride
    2. Propanamide
    3. Propanoic acid
    4. Propanone
61. The bacteria responsible for nitrification are:
    1. Clostridium
    2. Azotobacter
    3. Pseudomonas
    4. Nitrosomonas
62. The reaction of aldehydes and ketones with 2,4-DNP gives:
    1. Yellow precipitate
    2. Blue gas
    3. White fumes
    4. Black residue
63. Which ion forms white precipitate soluble in aqueous ammonia?
    1. Cl⁻
    2. Br⁻
    3. I⁻
    4. F⁻
64. The oxide of aluminum is:
    1. Strongly basic
    2. Amphoteric
    3. Acidic
    4. Strongly acidic
65. The most likely reaction alkanes undergo is:
    1. Electrophilic addition
    2. Nucleophilic addition
    3. Free radical substitution
    4. Electrophilic substitution
66. Which can donate an electron pair?
    1. RX
    2. RCOR
    3. RCHO
    4. $RNH_2$
67. The SI unit of amount of substance is:
    1. Gram
    2. Mole
    3. Liter
    4. Atom
68. 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
69. Heat of _______ a substance is always negative:
    1. Formation
    2. Combustion
    3. Decomposition
    4. Solution
70. Which human activity is the largest consumer of freshwater, placing stress on local water supplies?
    1. Industrialization
    2. Deforestation
    3. Agricultural development
    4. Mining
71. 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
72. Which halide ion has the strongest reducing power?
    1. F⁻
    2. Cl⁻
    3. Br⁻
    4. I⁻
73. Which of the following shows hydrogen bonding?
    1. CH4
    2. H2S
    3. H2O
    4. CO2
74. Retrosynthetic analysis is also known as:
    1. Deconstruction
    2. Dehydration
    3. Oxidation
    4. Hydrolysis
75. The structure of SO₂ molecule is:
    1. Linear
    2. Trigonal planar
    3. Bent
    4. Octahedral
76. The pH range of phenolphthalein is:
    1. 46025
    2. 3.5-5.5
    3. 46244
    4. 46180
77. The equation representing Einstein's mass-energy relation is:
    1. E = ½mv²
    2. E = mc²
    3. E = hf
    4. E = Pt
78. Formation of esters from alcohols and acids is called:
    1. Reduction
    2. Esterification
    3. Dehydration
    4. Polymerization
79. Which of these is NOT an adverse effect of air pollution on the environment?
    1. Disruption of ecosystem
    2. Increased agricultural productivity
    3. Damage to buildings and monuments
    4. Loss of biodiversity
80. 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