1. Which of the following halogens is a component of bleach? A. Iodine B. Chlorine C. Fluorine D. Bromine
2. Which nitrogen compound is responsible for the green color in some plant fertilizers? A. Urea (NH₂CONH₂) B. Ammonium nitrate (NH₄NO₃) C. Ammonium sulfate (NH₄)₂SO₄ D. Nitric acid (HNO₃)
3. Which heavy metal is used in the production of antifouling paints for ships? A. Mercury B. Copper C. Arsenic D. Lead
4. Which halogen is commonly used as a sterilizing agent for medical equipment? A. Iodine B. Fluorine C. Chlorine D. Bromine
5. Which metal is used in the production of surgical instruments due to its non-reactive nature? A. Platinum B. Nickel C. Zinc D. Copper
7. Which halogen is most commonly used in water fluoridation? A. Iodine B. Chlorine C. Fluorine D. Bromine
8. What is the primary use of hydrogen peroxide (H₂O₂)? A. As a disinfectant B. As an oxidizing agent C. As a reducing agent D. All of the above
9. The compound KMnO₄ is named as: A. Potassium manganate B. Potassium permanganate C. Potassium manganese oxide D. Potassium hypomanganate
11. The process by which water is purified using activated charcoal is called: A. Filtration B. Distillation C. Absorption D. Ion-exchange
12. Which of the following metals reacts with water to form hydrogen gas and hydroxide? A. Sodium B. Iron C. Copper D. Magnesium
14. Which of the following ores is the primary source of chromium? A. Bauxite B. Magnetite C. Chromite D. Cassiterite
16. Which of the following metals is NOT commonly found in the human body? A. Lead B. Zinc C. Iron D. Copper
17. What is the main product when nitrogen dioxide (NO₂) reacts with water? A. Nitric acid (HNO₃) B. Nitrous acid (HNO₂) C. Ammonium nitrate (NH₄NO₃) D. Nitric oxide (NO)
18. Which nitrogen compound is a major component of smog? A. Nitrogen dioxide (NO₂) B. Nitric oxide (NO) C. Nitrous oxide (N₂O) D. Ammonia (NH₃)
21. Which metal, symbolized by 'Ag', is known for its high conductivity and is used in electrical wiring? A. Gold B. Silver C. Copper D. Aluminum
22. Which of the following is a common use of sodium hydroxide (NaOH)? A. In the preparation of hydrochloric acid B. In the manufacture of soap C. In the preparation of sodium carbonate D. In the preparation of sulfuric acid
23. Which of the following compounds is used in disinfecting water? A. Ozone B. Hydrogen peroxide C. Sulfur dioxide D. Sulfur hexafluoride
24. What is the name of the compound with the formula MnO₂? A. Manganese(IV) oxide B. Manganese(III) oxide C. Manganese(II) oxide D. Manganese(VII) oxide
25. Which of the following is the most toxic form of arsenic? A. Arsenic trioxide B. Arsenic pentoxide C. Arsenic sulfide D. Arsenic chloride
26. Which of the following statements about water is true? A. Water is a non-polar molecule B. Water forms hydrogen bonds C. Water is insoluble in salts D. Water does not conduct electricity
29. Which of the following is true about the density of ozone compared to dioxygen? A. Ozone is denser than dioxygen B. Ozone is less dense than dioxygen C. Both have the same density D. Ozone is more reactive
31. Which of the following nitrogen compounds is commonly used in anesthesia? A. Ammonia (NH₃) B. Nitrous oxide (N₂O) C. Nitrogen dioxide (NO₂) D. Nitric acid (HNO₃)
34. Why does water have a high boiling point compared to other molecules of similar size? A. Because it has a high molecular mass B. Because of hydrogen bonding C. Because it is a non-polar molecule D. Because it forms strong covalent bonds
35. What is the chemical name of Cr₂O₃? A. Chromium(III) oxide B. Chromium(IV) oxide C. Chromium(II) oxide D. Chromium oxide
37. Water can dissolve both ionic and polar substances due to its: A. Non-polarity B. Hydrogen bonding C. Ionization D. Electronegativity
38. The high heat of vaporization of water plays a key role in: A. Thermoregulation in organisms B. Increasing the temperature of aquatic environments C. Decreasing the freezing point of water D. Increasing the temperature of water to boiling point
39. What is the name of the compound with the formula Al₂O₃? A. Aluminum oxide B. Aluminum hydroxide C. Aluminum chloride D. Aluminum sulfate
40. In the extraction of iron in a blast furnace, what gas is produced as a by-product? A. Oxygen B. Nitrogen C. Carbon monoxide D. Hydrogen
41. The IUPAC name of NH₄Cl is: A. Ammonium chloride B. Ammonia chloride C. Nitrogen chloride D. Ammonium chlorine
42. What is the common use of titanium in the industrial sector? A. Aircraft manufacturing B. Chemical plants C. Electrical wiring D. Paint production
43. Which of these ores is used for the extraction of aluminum? A. Magnetite B. Bauxite C. Chalcopyrite D. Malachite
45. Which process is responsible for converting nitrate ions (NO₃⁻) back into nitrogen gas (N₂) in the nitrogen cycle? A. Denitrification B. Ammonification C. Nitrification D. Nitrogen fixation
46. Which of the following is a major use of sulfur dioxide? A. In the preparation of sulfuric acid B. As a bleaching agent C. In disinfecting D. All of the above
47. Which of the following water pollutants can be removed by distillation? A. Heavy metals B. Organic contaminants C. Bacteria D. Salt
48. What is the process of removing impurities from an impure metal by electrolysis called? A. Electrorefining B. Leaching C. Smelting D. Roasting
49. Which of the following is the correct formula for chromium(III) chloride? A. CrCl₃ B. Cr₂Cl₃ C. CrCl₂ D. Cr₃Cl₆
50. Which metal is used in the production of batteries for electric cars? A. Lead B. Mercury C. Lithium D. Copper