Full Test

1. The process of DNA replication occurs in which part of the cell cycle?

A. G1 phase B. S phase C. G2 phase D. M phase

2. Which algae is considered a good source of agar?

A. Polysiphonia B. Chlorella C. Spirogyra D. Fucus

3. What is the key role of decomposers in an ecosystem?

A. To break down dead organic matter B. To consume primary producers C. To capture sunlight for energy D. To produce oxygen

4. Which of the following best describes the effect of noise pollution on animal behavior?

A. It enhances communication B. It has no effect on animals C. It disrupts communication and navigation D. It improves hunting success

5. Which part of the plant contains meristematic tissue?

A. Root tip B. Stem C. Leaf D. Flower

6. What is the primary cause of the extinction of species?

A. Natural selection B. Environmental change and competition for resources C. Genetic drift D. Gene flow

7. Which type of muscle tissue is found in the walls of the stomach?

A. Cardiac muscle B. Skeletal muscle C. Smooth muscle D. All of the above

8. Which bryophyte structure performs water absorption?

A. Rhizoids B. Root hairs C. Leaves D. Stem

9. Which of the following animals has a cartilaginous skeleton?

A. Sharks B. Rats C. Frogs D. Fish

10. What is the term for the gradual development of life forms from simple to complex organisms over time?

A. Natural selection B. Evolution C. Abiogenesis D. Adaptive radiation

11. C₄ plants reduce photorespiration by:

A. Closing stomata B. Spatial separation C. Temporal separation D. Lack of RuBisCO

12. Tobacco mosaic virus affects

A. animals B. bacteria C. plants D. fungi

13. Which of the following is a significant cause of declining forest cover in Nepal?

A. Illegal logging B. Overgrazing by livestock C. Natural disasters D. Overpopulation

14. Which of the following is an example of an X-linked recessive disorder?

A. Down syndrome B. Hemophilia C. Cystic fibrosis D. Huntington's disease

15. Which type of epithelial tissue is found in the lining of the digestive tract?

A. Columnar epithelium B. Squamous epithelium C. Cuboidal epithelium D. Transitional epithelium

16. Which of the following groups of animals has a three-chambered heart?

A. Mammals B. Amphibians C. Reptiles D. Birds

17. Which type of epithelial tissue lines the small intestine?

A. Simple columnar epithelium B. Stratified squamous epithelium C. Simple cuboidal epithelium D. Transitional epithelium

18. Which of the following pollutants is most commonly associated with the depletion of the ozone layer?

A. Carbon monoxide B. Chlorofluorocarbons (CFCs) C. Methane D. Nitrous oxide

19. Which type of epithelial tissue is specialized for filtration?

A. Squamous epithelium B. Cuboidal epithelium C. Columnar epithelium D. Transitional epithelium

20. Which of the following is the vector for the transmission of Plasmodium?

A. Tsetse fly B. Mosquito C. Flea D. Tick

21. Which of the following is the most diverse ecosystem in Nepal?

A. Tropical Forest B. Temperate Forest C. Alpine Forest D. Wetlands

22. The enzyme RuBisCO helps in:

A. ATP formation B. Water splitting C. CO₂ fixation D. Oxygen release

23. What is the main cause of cystic fibrosis?

A. Defect in the CFTR gene leading to faulty chloride ion transport B. Deficiency of the enzyme amylase in the pancreas C. Mutation in the hemoglobin gene D. Defective insulin production in the pancreas

24. The basic unit of life is?

A. Cell B. Atom C. Organism D. Tissue

25. Pleiotropy means:

A. One gene, many traits B. Many genes, one trait C. Linked genes D. Polyploidy

26. Which part of the frog’s body is responsible for the elimination of waste?

A. Kidneys B. Bladder C. Cloaca D. Liver

27. In which phase of mitosis do the chromatids separate?

A. Metaphase B. Anaphase C. Telophase D. Prophase

28. Which of the following is a key characteristic of prokaryotic organisms?

A. They lack membrane-bound organelles B. They have a defined nucleus C. They can perform photosynthesis D. They have linear DNA

29. Which cell type in leaf lacks chloroplast but regulates photosynthesis indirectly?

A. Spongy mesophyll B. Guard cells C. Epidermal cells D. Bundle sheath cells

30. Which type of epithelial tissue is found in the skin?

A. Stratified squamous epithelium B. Columnar epithelium C. Cuboidal epithelium D. Simple squamous epithelium

31. Which of the following is a common risk factor for developing kidney disease?

A. Regular exercise B. Chronic high blood pressure C. Adequate hydration D. Low cholesterol

32. Which of the following refers to an organism with two identical alleles for a gene?

A. Homozygous dominant B. Heterozygous C. Homozygous recessive D. Heterozygous recessive

33. Which of the following is true about the cambium layer in plants?

A. It is responsible for primary growth B. It is responsible for secondary growth C. It stores food D. It is found in the roots

34. Which of the following is a characteristic of all living organisms?

A. Ability to respond to stimuli B. Ability to move C. Ability to photosynthesize D. Ability to produce heat

35. Which of the following mechanisms does the immune system use to fight cancer cells?

A. Cytotoxic T lymphocytes (CTLs) recognize and kill tumor cells by releasing perforin and granzymes B. Natural killer (NK) cells kill tumor cells that downregulate MHC class I expression C. Macrophages release cytokines and enzymes that target tumor cells D. All of the above

36. Which type of epithelial tissue is involved in absorption?

A. Squamous epithelium B. Columnar epithelium C. Cuboidal epithelium D. Transitional epithelium

37. What is the main function of the spleen in the human body?

A. Filter blood and recycle iron from red blood cells B. Store bile for digestion C. Produce white blood cells for the immune response D. Regulate blood sugar levels

38. Which of the following tissues is the main component of skin?

A. Epithelial tissue B. Connective tissue C. Muscle tissue D. Nervous tissue

39. Which of the following is responsible for the phototropism response in plants?

A. Cytokinins B. Auxins C. Abscisic acid D. Gibberellins

40. Which of the following is the main benefit of genetic modification of crops?

A. Increased resistance to pests B. Decreased nutritional value C. Increased water requirement D. Decreased disease resistance

41. Which of the following is an example of an animal using camouflage to avoid predators?

A. Chameleons blending with leaves B. Polar bears blending with snow C. Octopuses changing color D. All of the above

42. Which of the following processes is triggered by light in plants?

A. Photosynthesis B. Respiration C. Germination D. Transpiration

43. Unicellular non-motile algae is

A. Chlorella B. Volvox C. Chlamydomonas D. Euglena

44. Which of the following is the primary cause of ozone layer depletion?

A. Chlorofluorocarbons (CFCs) B. Carbon dioxide C. Methane D. Nitrous oxide

45. What is the term for the specialized region of the chromosome where spindle fibers attach?

A. Centromere B. Chromatid C. Telomere D. Centrosome

46. Which of the following phyla consists of animals with bilateral symmetry?

A. Platyhelminthes B. Porifera C. Cnidaria D. Echinodermata

47. What is the cause of the genetic disorder Huntington’s disease?

A. A repeat expansion in the CAG sequence of the huntingtin gene B. Deletions in the PINK1 gene affecting mitochondrial function C. Excessive phosphorylation of tau proteins in the brain D. Mutations in the PTEN gene, leading to defective tumor suppression

48. Which of the following is the most significant effect of soil pollution?

A. Decreased fertility B. Increased crop yield C. Enhanced water retention D. Improved soil structure

49. Which virus shows complex symmetry?

A. TMV B. Influenza C. Bacteriophage D. Polio

50. In which phylum are organisms like starfish and sea urchins classified?

A. Arthropoda B. Echinodermata C. Mollusca D. Annelida

51. Which of the following is an example of incomplete dominance?

A. Red and white flowers producing pink offspring B. A type blood resulting from the inheritance of one A allele and one B allele C. A red and blue fish producing purple offspring D. Two dominant traits appearing together

52. Which of the following is a characteristic feature of the phylum Echinodermata?

A. Bilateral symmetry B. Exoskeleton C. Water vascular system D. Radial symmetry in larvae

53. Which of the following animals is cold-blooded?

A. Lion B. Shark C. Human D. Frog

54. What is the function of the human immune system?

A. Regulate blood pressure B. Protect the body from harmful pathogens C. Produce digestive enzymes D. Help in food digestion

55. Which of the following cells in xylem are living at maturity?

A. Tracheids B. Vessels C. Xylem parenchyma D. Xylem fibres

56. Which of the following is a function of the human skeletal system?

A. Production of insulin B. Support and protect internal organs C. Production of blood cells D. Both B and C

57. The conservation of which of the following species is essential for maintaining forest ecosystem health in Nepal?

A. One-horned rhinoceros B. Bengal tiger C. Red panda D. All of the above

58. Which part of flower is a modified leaf?

A. Sepal B. Petal C. Stamen D. All of these

59. Which of the following is the most significant effect of aging on the immune system?

A. Decreased production of new T-cells and B-cells B. Increased production of antibodies C. Improved ability to fight infections D. Faster wound healing

60. Which structure in the frog’s digestive system absorbs water and minerals?

A. Small intestine B. Large intestine C. Stomach D. Liver

61. How does the accumulation of reactive oxygen species (ROS) contribute to the pathophysiology of neurodegenerative diseases like Alzheimer's?

A. ROS cause oxidative damage to cellular components, including lipids, proteins, and DNA B. ROS stimulate the overproduction of amyloid plaques in the brain C. ROS impair mitochondrial function, leading to energy deficiency in neurons D. ROS activate inflammatory pathways that lead to neuronal death

62. Which of the following is true for prokaryotic cells?

A. They have a nucleus B. They lack ribosomes C. They have no membrane-bound organelles D. They are multicellular

63. What is the concept of 'fitness' in evolutionary biology?

A. The ability of an organism to survive and reproduce in its environment B. The physical strength of an organism C. The speed of an organism’s growth D. The ability of an organism to adapt to environmental changes

64. The direction of food transport in phloem is:

A. Always upward B. Always downward C. Bidirectional D. Only during night

65. What is the primary purpose of meiosis?

A. To create genetically identical cells B. To produce cells for growth C. To create gametes with half the number of chromosomes D. To replicate DNA

66. Which of the following tissues is involved in protection, absorption, and secretion?

A. Epithelial tissue B. Connective tissue C. Muscle tissue D. Nervous tissue

67. Which class of Chordates is characterized by the presence of gills throughout life?

A. Amphibia B. Reptilia C. Mammalia D. Pisces

68. Maximum transpiration occurs when stomata are:

A. Closed B. Partially open C. Fully open D. Absent

69. Which of the following describes the role of abscisic acid in plants?

A. It regulates stomatal closure during water stress B. It promotes seed germination C. It stimulates root growth D. It induces flowering

70. Which type of pollution is caused by excess heat in aquatic ecosystems?

A. Water pollution B. Thermal pollution C. Noise pollution D. Air pollution

71. Heterochromatin is:

A. Transcriptionally active B. Light stained C. Densely packed D. Functional

72. Which of the following gases is a major contributor to acid rain?

A. Oxygen B. Nitrogen C. Carbon dioxide D. Sulfur dioxide

73. Which part of the body is most affected by Parkinson's disease?

A. Muscles B. Lungs C. Brain D. Kidneys

74. Which of the following is a major consequence of air pollution?

A. Climate change B. Overpopulation C. Increased food production D. Soil erosion

75. Which structure in an earthworm aids in absorbing water from the soil?

A. Setae B. Skin C. Clitellum D. Gizzard

76. Which of the following organs does Plasmodium infect in humans?

A. Liver B. Stomach C. Brain D. Kidneys

77. Which of the following is true about the adaptation of animals to extreme temperatures?

A. They change their behavior to regulate body temperature B. They migrate to different climates C. They have specialized body structures D. All of the above

78. Which venation indicates dicot?

A. parallel B. reticular C. circular D. none

79. Which part of the human brain is responsible for controlling voluntary movements?

A. Cerebellum B. Medulla oblongata C. Cerebrum D. Thalamus

80. Bryophytes are poikilohydric, which means?

A. They regulate water internally B. They depend on external water C. They store water D. They produce water

81. Which force keeps a stone moving in a circular path when tied to a string?

A. Centrifugal B. Tension C. Friction D. Gravity

82. In an RLC circuit, the phase difference between the total voltage and total current is:

A. Zero at resonance B. 90° at resonance C. 180° at resonance D. 180° at maximum frequency

83. Which of the following factors does NOT influence the force experienced by a charged particle in a magnetic field?

A. The strength of the magnetic field B. The speed of the particle C. The charge of the particle D. The temperature of the particle

84. The time period of SHM depends on:

A. Amplitude only B. Mass and force constant C. Velocity D. Energy

85. An insect crawls a distance of 4m along north in 10 seconds and then a distance of 3m along east in 5 seconds. The average velocity of the insect is (in m/s)

A. 7/15 B. 1/5 C. 5/15 D. 12/15

86. The dimension of impulse are equal to that of

A. pressure B. linear momentum C. force D. angular momentum

87. Which of the following statements is correct about nuclear energy?

A. It uses high-temperature gases to produce electricity B. It releases large amounts of carbon dioxide C. It is generated by breaking apart heavy atomic nuclei D. It is generated by fusing light atomic nuclei

88. Which of the following is true for an induced current?

A. It always flows in a direction that opposes the change in flux B. It always flows in a direction that reinforces the change in flux C. It flows only when the magnet is stationary D. It is always proportional to the current flowing in the coil

89. The photoelectric effect provides evidence that light has

A. A constant speed B. A dual nature (wave-particle nature) C. No mass D. Mass as large as electrons

90. The reflection of sound waves from a hard surface is known as:

A. Echo B. Diffraction C. Refraction D. Interference

91. If a charge is placed at the origin, the electric potential at a distance r from the charge is given by:

A. kQ/r B. kQ/r² C. kQ²/r D. k/r

92. Quantity having dimensions M⁰L⁰T⁰ is:

A. Stress B. Strain C. Pressure D. Force

93. Hooke's law is valid up to:

A. Elastic limit B. Yield point C. Breaking point D. Plastic region

94. Which of the following is the correct expression for Coulomb’s Law?

A. F = kq1q2/r B. F = kq1q2r C. F = q1q2/r^2 D. F = q1q2r^2

95. Which of the following is an application of polarization?

A. Sunglasses B. X-ray imaging C. Sound wave detection D. Microwave cooking

96. The energy levels in an atom are quantized, which means:

A. Electrons can occupy any energy level B. Electrons can occupy only fixed energy levels C. Electrons can occupy energy levels between two fixed values D. Energy levels are continuously distributed

97. Rolling without slipping condition is:

A. v = rω B. v = r/ω C. v = ω/r D. v = r²ω

98. The electric field due to a point charge decreases with:

A. The square of the distance B. The cube of the distance C. The distance itself D. The square root of the distance

99. The frequency of SHM is:

A. 1/T B. T/2π C. 2πT D. ωT

100. The velocity of sound in a gas is dependent on which of the following?

A. Mass of the gas molecules B. Density of the gas C. Temperature of the gas D. All of the above

101. The relation between torque and angular acceleration is:

A. τ = Iω B. τ = Iα C. τ = ω/I D. τ = α/I

102. Unit of specific heat in SI is:

A. Cal/g B. J/kg·K C. Cal/kg·C D. J/kg·°C

103. A prism produces a spectrum because?

A. Refractive index varies with wavelength B. The prism absorbs light C. All wavelengths bend equally D. Light spreads randomly

104. In an AC circuit with an inductor, the voltage leads the current by:

A. 90° B. 60° C. 0° D. 180°

105. In a P-type semiconductor, which of the following is the majority charge carrier?

A. Electrons B. Holes C. Neutrons D. Protons

106. To form a real image using a convex lens, the object must be placed?

A. At infinity B. At F C. Between F and 2F D. At the center of curvature

107. The induced current in a closed loop depends on:

A. The time rate of change of magnetic flux B. The area of the loop C. The resistance of the coil D. All of the above

108. In a heating element, the resistance is increased to

A. Increase current flow B. Decrease the heat produced C. Increase the heat produced D. Regulate temperature

109. One mole of an ideal gas at STP occupies

A. 22.4 L B. 24 L C. 20 L D. 25 L

110. Static pressure is:

A. Pressure exerted by fluid at rest B. Pressure due to motion C. Pressure difference D. Pressure gradient

111. The direction of the electric field at any point in space is:

A. Always parallel to the surface of a conductor B. Always perpendicular to the surface of a conductor C. Always radial to the point charge D. Random and can be in any direction

112. Total internal reflection does not occur when

A. Light goes from denser to rarer medium and incidence < critical angle B. Light goes from denser to rarer medium and incidence > critical angle C. Light goes from denser to rarer medium at critical angle D. Light goes from denser to rarer medium at normal incidence

113. Thermoelectric power generation is efficient when

A. There is a small temperature gradient B. There is no temperature gradient C. There is a large temperature gradient D. None of the above

114. At extreme position of SHM, acceleration is:

A. Zero B. Minimum C. Maximum D. Constant

115. Which quantity remains constant in SHM (ideal case)?

A. Velocity B. Acceleration C. Total energy D. Momentum

116. In a tank, liquid level falls faster if:

A. Hole area increases B. Fluid density increases C. Gravity decreases D. Viscosity increases

117. A person can throw a ball a maximum distance d over a ground. What is the maximum vertical height to which he can throw?

A. d B. d/2 C. d/4 D. 2d

118. A bullet is fired into a block. Its K.E. reduces by 50% in penetrating the block through 9cm. What is the total distance penetrated by the bullet?

A. 10cm B. 12cm C. 15cm D. 18cm

119. Which device works based on total internal reflection?

A. Prism B. Concave lens C. Convex lens D. Slit

120. In the hydrogen atom, the electron transition from n = 2 to n = 1 produces which type of light?

A. Infrared B. Visible C. Ultraviolet D. X-rays

121. In wet and dry bulb hygrometer, wet bulb shows:

A. Temperature of saturated air B. Lower temperature due to evaporation C. Higher temperature D. Ambient temperature

122. A thermocouple consists of two wires of different materials. The difference in their behavior is due to

A. Their different electrical resistances B. The difference in their thermal conductivities C. Their different densities D. The difference in the Seebeck coefficients

123. The focal length of a lens is related to its power by the formula?

A. P = f/1 B. P = 1/f C. P = f D. None of these

124. During isothermal compression of an ideal gas, the work done on gas is

A. Negative B. Zero C. Positive D. Depends on temperature

125. The dielectric constant of a material is defined as the ratio of

A. Electric field with dielectric to electric field without dielectric B. Capacitance with dielectric to capacitance without dielectric C. Energy stored with dielectric to energy stored without dielectric D. None of the above

126. Which force is responsible for the attraction between objects due to their masses?

A. Electromagnetic force B. Gravitational force C. Strong nuclear force D. Weak nuclear force

127. Magnetic flux is the product of?

A. Magnetic field strength and the area through which the field passes B. Magnetic field strength and the current in the conductor C. Current and resistance D. Area and resistance

128. Which of the following is a fundamental force of nature?

A. Friction B. Electromagnetic force C. Elastic force D. Buoyant force

129. The effusion rate of gas is inversely proportional to

A. Square root of density B. Square root of molar mass C. Pressure D. Volume

130. If the intensity of light is increased in the photoelectric effect,

A. The energy of the emitted electrons increases B. The number of emitted electrons increases C. The frequency of emitted electrons increases D. The maximum kinetic energy of emitted electrons increases

131. Which of the following is the correct pH range for an acidic solution?

A. pH < 7 B. pH > 7 C. pH = 7 D. None of the above

132. Which of the following compounds will undergo polymerization to form polyethylene?

A. Ethene B. Propene C. Butene D. Methane

133. Which of the following metals is NOT considered a heavy metal?

A. Copper B. Mercury C. Sodium D. Cadmium

134. Which of the following ores is a source of cobalt?

A. Chalcopyrite B. Cobaltite C. Bauxite D. Zincite

135. What is the atomic number of Neon?

A. 10 B. 12 C. 14 D. 18

136. Which of the following happens when a gas is cooled at constant pressure?

A. Its volume increases B. Its volume decreases C. Its pressure increases D. Its temperature decreases

137. The reaction of water with Na metal forms which of the following products?

A. NaOH and H₂ B. Na₂O and H₂ C. NaCl and H₂O D. NaOH and Cl₂

138. Which of the following reactions shows the highest oxidation state of oxygen?

A. 2O₂ → 2O₃ B. O₂ + 2H₂ → 2H₂O C. SO₂ + O₂ → SO₃ D. H₂O₂ → H₂O + O₂

139. What is the functional group of an aldehyde?

A. –OH B. –CHO C. –COOH D. –C=O

140. Which of the following compounds is an alkane?

A. C5H8 B. C2H4 C. C8H18 D. C3H6

141. Which of the following is true about the reactivity of amines compared to carboxylic acids?

A. Amines are more basic B. Amines are less basic C. Amines are stronger acids D. Amines do not react with acids

142. What is the main difference between chain isomerism and positional isomerism?

A. Chain isomerism involves different carbon chains B. Positional isomerism involves different positions of functional groups C. Chain isomerism involves functional group changes D. Positional isomerism involves different molecular formulas

143. Which of the following is the correct name for Cr₂O₃?

A. Chromium(III) oxide B. Chromium(II) oxide C. Chromium(VI) oxide D. Chromium(IV) oxide

144. If the concentration of a product is increased in a reaction at equilibrium, what happens to the equilibrium position?

A. The equilibrium will shift to the right B. The equilibrium will shift to the left C. The equilibrium will remain unchanged D. The equilibrium constant will decrease

145. Which of the following is not a property of sodium hydroxide (NaOH)?

A. It is highly soluble in water B. It is a strong base C. It is corrosive D. It is an acidic compound

146. Which of the following properties of water is essential for its role in regulating temperature in living organisms?

A. Its low boiling point B. Its high heat of vaporization C. Its high conductivity D. Its high pH

147. Which of the following reactions leads to the formation of a carboxylic acid from an alcohol?

A. Oxidation with K2Cr2O7 B. Reduction with NaBH4 C. Addition of HCl D. Nitration

148. Which of these elements has the highest second ionization energy?

A. Sodium B. Magnesium C. Aluminum D. Silicon

149. The work done by an ideal gas in an isochoric process is:

A. Zero B. nRT C. P∆V D. Q

150. Which of the following ions has the electron configuration of 1s² 2s² 2p⁶ 3s² 3p⁶?

A. K⁺ B. Na⁺ C. Ca²⁺ D. Mg²⁺

151. What is the pH of a 0.1 M H₂SO₄ solution (strong diprotic acid)?

A. 1 B. 2 C. 3 D. 4

152. How many milliliters of 0.1 M NaOH are required to neutralize 25 mL of 0.2 M HCl?

A. 25 mL B. 50 mL C. 75 mL D. 100 mL

153. Which of the following is true about the rate of a chemical reaction?

A. It is constant for all reactions B. It depends only on the temperature C. It is independent of the concentration of reactants D. It depends on the concentration of reactants

154. The energy of a galvanic cell can be calculated using which equation?

A. E = -RT/nF ln(K) B. E = -nF Q C. E = E°cell - (0.0592/n) log Q D. E = E°cell + (0.0592/n) log Q

155. Which halogen is most commonly used in water fluoridation?

A. Iodine B. Chlorine C. Fluorine D. Bromine

156. In the molecule H2O, how many sigma bonds are present?

A. 2 B. 3 C. 4 D. 1

157. Which of the following statements is true for ozone?

A. Ozone absorbs ultraviolet radiation B. Ozone is an essential component of air C. Ozone is a reducing agent D. All of the above

158. Which of the following is true about aromatic compounds?

A. They are highly reactive B. They contain a benzene ring C. They contain only single bonds D. They contain a carbonyl group

159. Which of the following can increase the solubility of a gas in water?

A. Decreasing pressure B. Increasing temperature C. Decreasing temperature D. Decreasing gas concentration

160. Which of the following compounds is used as a bleaching agent?

A. SO₂ B. Cl₂ C. O₃ D. All of the above

161. Which of these is NOT a part of the electrochemical cell?

A. Salt bridge B. Electrodes C. Electrolyte D. Transformer

162. Which of the following molecules has an octahedral molecular geometry?

A. SF6 B. PCl5 C. CO2 D. SO2

163. The IUPAC name for the compound CH₃CH₂CHO is:

A. Ethyl aldehyde B. Ethanol C. Ethanal D. Propionaldehyde

164. What is the effect of dilution on the normality of an acid or base solution?

A. It increases B. It decreases C. It remains the same D. It becomes zero

165. Which halogen is present in table salt (NaCl)?

A. Fluorine B. Chlorine C. Bromine D. Iodine

166. Which metal is represented by the symbol 'Hg'?

A. Mercury B. Hydrogen C. Helium D. Hafnium

167. Which of the following compounds is an example of an aromatic compound?

A. Toluene B. Methane C. Ethanol D. Butane

168. What is the IUPAC name of the compound C₆H₆O?

A. Phenol B. Benzene C. Benzyl alcohol D. Toluene

169. The main structural component of cell membranes is:

A. Proteins B. Carbohydrates C. Lipids D. Nucleic acids

170. Which of the following is a characteristic of haloalkanes?

A. They contain a halogen atom B. They are non-polar C. They do not react with water D. They are weak acids

171. Which of the following is true about nitrogen in its elemental form (N₂)?

A. It is highly reactive B. It is inert and unreactive C. It is a strong oxidizing agent D. It is a strong reducing agent

172. Sodium reacts with acids to form:

A. Salt and hydrogen gas B. Salt and oxygen gas C. Salt and water D. Salt and sodium hydroxide

173. Which element has a lower electron affinity than nitrogen?

A. Fluorine B. Oxygen C. Phosphorus D. Chlorine

174. Which of the following molecules exhibits sp^3 hybridization on its central atom?

A. CO2 B. CH4 C. SO3 D. C2H2

175. What is the mass of 0.5 moles of ammonia (NH3)?

A. 8 g B. 17 g C. 34 g D. 51 g

176. What is the oxidation state of nitrogen in NH₄⁺?

A. +3 B. +2 C. +1 D. -3

177. What is the boiling point of water at 1 atm pressure?

A. 100°C B. 90°C C. 110°C D. 105°C

178. How many electrons are there in a neutral atom of sodium? (Atomic number = 11)

A. 12 B. 13 C. 11 D. 10

179. How many moles of HCl are needed to neutralize 0.05 moles of NaOH?

A. 0.05 moles B. 0.1 moles C. 0.2 moles D. 0.25 moles

180. The compound CH₃CH₂COOH is known as:

A. Ethanoic acid B. Acetic acid C. Propanoic acid D. Butanoic acid