13. The reaction at cathode during the electrolysis of aqueous solution of \(NaCl\) is:
\(2H^+ + 2e^- → H_2\)
\(Na^+ + e^- → Na\)
\(2Cl^- → Cl_2 + 2e^-\)
\(2H_2O + 2e^- → H_2 + 2OH^-\)
(d) In NaCl electrolysis, water is reduced at cathode: \(2H_2O + 2e^- → H_2 + 2OH^-\).
14. If the rate of reaction becomes twice for every 10°C rise in temperature, by what factor rate of reaction increases when temperature is increased from 25°C to 75°C?
27. Which one of the following complex compound has an incorrect formula?
Diamine Silver Chloride - \([Ag(NH_3)_2]Cl\)
Ferric Ferro Cyanide - \(Fe_4[Fe(CN)_6]\)
Azure blue complex of Copper Sulphate \([Cu(NH_3)_4]SO_4\)
Sodium Nitropruside - \(Na_2[Fe(CN)_5NO]\)
(b) Correct formula is \(Fe_4[Fe(CN)_6]_3\) (Ferric ferrocyanide).
28. Which of the following are Isomers?
Propanoic acid and Methyl methanoate
Methyl alcohol and Dimethyl ether
Acetone and Acetaldehyde
Ethyl alcohol and Dimethyl ether
(d) Both \(C_2H_5OH\) and \(CH_3OCH_3\) have molecular formula \(C_2H_6O\).
29. A solution of Sodium in liquid Ammonia is blue due to the presence of:
Solvated electrons
Solvated Sodium ions
Ammonium ions
Sodium atoms
(a) The blue color comes from solvated electrons (\(e^-(NH_3)\)).
30. Which of the following electronic configuration given for some neutral atoms would be expected to have highest second ionization energy \(IE_2\)?
\(1s^2 2s^2\)
\(1s^2 2s^2 2p^4\)
\(1s^2 2s^2 2p^1\)
\(1s^2 2s^2 2p^3\)
(a) \(Be^+\) (\(1s^2 2s^1\) after 1st ionization) has highest \(IE_2\) due to small size + full \(1s^2\) core.
31. When temperature of gas is increased its viscosity:
Remains constant
Increases
Decreases
First decreases then increases
(b) Gas viscosity increases with temperature (unlike liquids) due to increased molecular motion.
32. The maximum wavelengths, emitted by the sun at the temperatures (in Kelvin) T1, T2 and T3 are 650 nm, 580 nm and 350 nm respectively. Which one of the following is correct?
T1 > T2; T1 > T3
T3 > T1; T3 > T2
T2 > T1; T2 > T3
T1 = T2 = T3
(b) From Wien's law (\(λ_{max} ∝ 1/T\)), shortest λ (350 nm) corresponds to highest T (T3).
33. Two ebonite rods A and B of radii 1.5cm and 2cm respectively are rubbed together. The result will be:
A and B both remain neutral
A will be charged positively
A will be charged negatively
Both A and B will be charged equally with similar charge
(c) Smaller radius (A) gains more negative charge due to higher curvature.
34. Power of ionization of a gamma particle is:
More than that of an alpha particle
More than that of a beta particle
Less than those of alpha beta particle and more than these of beta particle
Less than both alpha and beta particle
(d) Ionization power: α > β > γ (gamma has least ionization).
35. Activity of 1.85×1012 disintegration per second is nearly equivalent to:
40 curie
30 curie
50 curie
60 curie
(c) 1 Ci = 3.7×1010 dps → 1.85×1012 dps ≈ 50 Ci.
36. The specific gravity of sugar is 1.59. Which is its correct density in S.I. system?
1.59
159
15.9
1590
(d) Density = specific gravity × 1000 kg/m³ = 1.59 × 1000 = 1590 kg/m³.
37. If a baseball player can throw a ball to maximum distance = d over a ground, what is the maximum vertical height to which he can throw it? (Assume same initial speed):
d
d/4
d/2
2d
(c) Max range occurs at 45° (d = v²/g). Max height (90°) is v²/2g = d/2.
38. When an elastic material with Young's modulus 'Y' is subjected to a stretching stress 'S', the elastic energy stored per unit volume is:
YS²
S²/2Y
S²Y/2
S/2Y
(b) Elastic energy per unit volume = \( \frac{1}{2} × stress × strain = \frac{S^2}{2Y} \).
39. Two drops of water having same radius moving in air downwards with constant velocity v. If the drops coalesced, what will be the new velocity:
40. The radius of hydrogen atom in the ground state is 0.53 Å. After excitation, it is found that this radius increases to 2.12 Å. The value of principal quantum number will be:
5
3
4
2
(d) rn = n²r1 → n² = 2.12/0.53 = 4 → n = 2.
41. What is the value of -40 Fahrenheit in Celsius scale?
-104°C
8°C
-40°C
20°C
(c) -40°F = -40°C (the scales intersect at this point).
42. What is the potential drop across an electric hot plate which draws 5 A when it is hot and resistance is 24Ω?
120V
140V
130V
150V
(a) V = IR = 5A × 24Ω = 120V.
43. A refrigerator has to transfer an average of 263J of heat per second from -10°C to 25°C. The average power consumed by the refrigerator is:
10W
20W
35W
40W
(c) Using COP = TL/(TH-TL) and W = QL/COP ≈ 35W.
44. A tube closed at one end containing air when excited produces the fundamental note of frequency 512 Hz. If the tube is open at both ends the fundamental frequency that can be excited is:
1024 Hz
256 Hz
512 Hz
128 Hz
(a) Open tube fundamental frequency is twice that of closed tube (same length).
45. The pendulum of clock is made of brass. If the clock keeps correct time at 20°C, how many seconds per day will it lose at 35°C? (αbrass = 2×10-5 °C-1)
12.3 secs
36.9 secs
24.6 secs
49.2 secs
(a) ΔT ≈ ½αΔθ × 86400 = ½ × 2×10-5 × 15 × 86400 ≈ 12.3 sec.
46. A body cools down from 65°C to 60°C in 5 minutes. It will cool down 60°C to 55°C in:
5 minutes
Less than 5 minute
More than 5 minutes
Less than or more than 5 minutes depending on whether its mass is more than or less than 1 kg
(c) Cooling rate decreases as ΔT decreases (Newton's law of cooling).
47. An object is placed at a distance 'u' from a simple microscope of focal length 'f'. The angular magnification obtained depends:
On 'f' but not on 'u'
On 'f' as well as 'u'
On 'u' but not on 'f'
Neither on 'f' nor on 'u'
(b) Angular magnification = (1 + D/f) when image at infinity, but depends on u for finite distances.
48. A parallel plate capacitor is charged and the charging battery is then disconnected. If the plates are moved further apart:
The charge on the capacitor increases
The voltage across the plate increases
The capacitance increases
The electrostatic energy stored in the capacitor decreases
(b) Q constant, C decreases (C ∝ 1/d) → V increases (V = Q/C).
49. A thin stream of water from a tap is attracted by placing a rod near it. The rod is:
The south pole of the magnet
Charged with static electricity
The north pole of the magnet
Any non-magnetic substance
(b) Charged rod induces polarization in water stream causing attraction.
50. If the current in an electric bulb drops by 2%, the power decreases by:
1%
4%
2%
16%
(b) P ∝ I² → ΔP/P ≈ 2(ΔI/I) → 2×2% = 4% decrease (for small changes).
51. Keratinized stratified squamous epithelium is found in:
Trachea
Lining of blood vessel
Mouth cavity
Epidermis
(d) The epidermis contains keratinized stratified squamous epithelium for protection against abrasion and water loss.
52. Histamine is secreted by:
Fibroblast
Mast cells
Chondroblast
Histocytes
(b) Mast cells release histamine during inflammatory responses.
53. Nematocysts in hydra paralyze prey by secreting a poisonous substance called:
Heparin
Hypnotoxin
Histamine
Neurotoxin
(b) Hypnotoxin is the neurotoxic substance in nematocysts that paralyzes prey.
54. Glucagon is a hormone secreted from:
Pineal body
Pancreas
Liver
Pituitary body
(b) Glucagon is produced by α-cells of pancreatic islets (Islets of Langerhans).
55. Elongated muzzle and backwardly inverted spines in the Porcupine are the characteristics of:
Aquatic adaptation
Amphibious adaptation
Volant adaptation
Fossorial adaptation
(d) These are adaptations for burrowing (fossorial life).
56. Skeleton and muscles in a vertebrate embryo develop from:
Ectoderm and Endoderm
Ectoderm only
Ectoderm and mesoderm
Mesoderm only
(d) Mesoderm gives rise to musculoskeletal system (somites → muscles, sclerotome → skeleton).
57. The most dangerous species of Plasmodium is:
Malariae
Ovale
Falciparum
Vivax
(c) P. falciparum causes malignant tertian malaria with highest mortality.
58. Graafian follicles are found in:
Testes
Stomach
Ovary
Spleen
(c) Graafian follicles are mature ovarian follicles containing secondary oocytes.
59. The bone of mammals contains longitudinal Haversian canals, which are connected by transverse canals called:
Bidder's canal
Volkmann's canal
Inguinal canal
Eustachian canal
(b) Volkmann's canals connect adjacent Haversian canals in compact bone.
60. Which animal has a free living mode of feeding or nutrition?
Plasmodium
Fasciola
Ancylostoma
Planaria
(d) Planaria (free-living flatworm) has autonomous feeding, unlike parasitic options.
61. Which animal Phylum has the characteristic of polymorphism?
Annelida
Porifera
Coelenterata
Protozoa
(c) Cnidaria (Coelenterata) shows polymorphism (e.g., polyp and medusa forms).
62. Which class of the Phylum Platyhelminthes has been assigned to Schistosoma?
Turbellaria
Cestoda
Trematoda
Digenea
(c) Schistosoma (blood fluke) belongs to Class Trematoda.
63. Water vascular system is a characteristic feature of the Phylum:
Annelida
Mollusca
Echinodermata
Chordata
(c) Unique to echinoderms (e.g., starfish) for locomotion and feeding.
64. The right auriculo-ventricular aperture in rabbit is guarded by:
Bicuspid valve
Spiral valve
Semilunar valve
Tricuspid valve
(d) Right AV valve is tricuspid; left is bicuspid (mitral).
65. Rete testis is part of:
Seminiferous tubules
Epididymis
Vasa efferentia
Vas deferens
(c) Rete testis connects seminiferous tubules to vasa efferentia.
66. Gigantism is caused due to hypersecretion of:
Pituitary gland
Adrenal gland
Thyroid gland
Thymus gland
(a) Excess growth hormone (GH) from anterior pituitary causes gigantism.
