Chemistry of Group 13_14_15 Elements II (Exercise) Welcome to your Chemistry of Group 13_14_15 Elements II (Exercise) May 9, 2024 Name Email 1. Which Group 13 element exhibits lower reactivity compared to aluminum? Boron (B) Aluminum (Al) Gallium (Ga) Indium (In) 2. When gallium reacts with a strong base, such as sodium hydroxide (NaOH), it forms which compound? Sodium tetrahydroxogallate Aluminum hydroxide Sodium tetrahydroxoaluminate Gallium nitrate 3. Indium slowly oxidizes when exposed to moist air and reacts with nonmetals to form compounds such as: Indium trichloride (InCl3) Indium oxide (In2O3) Gallium arsenide (GaAs) Gallium nitride (GaN) 4. Crystalline boron can exist in different crystal structures, including: α-rhombohedral and β-tetragonal boron β-rhombohedral and γ-tetragonal boron γ-rhombohedral and α-tetragonal boron β-rhombohedral and β-tetragonal boron 5. Which Group 13 element reacts with oxygen in the air to form a thin, transparent oxide layer that provides excellent corrosion resistance? Boron (B) Aluminum (Al) Gallium (Ga) Indium (In) 6. Indium reacts with nonmetals, such as halogens, to form compounds like: Indium trichloride (InCl3) Indium oxide (In2O3) Gallium arsenide (GaAs) Gallium nitride (GaN) 7. Thallium finds some use in specialized glass and high-temperature superconductors due to its: Low reactivity High reactivity Low density High density 8. Which Group 13 element has a low melting point near room temperature, making it valuable in high-temperature thermometers and heat transfer systems? Boron (B) Aluminum (Al) Gallium (Ga) Indium (In) 9. Which Group 13 element slowly oxidizes when exposed to moist air? Boron (B) Aluminum (Al) Gallium (Ga) Indium (In) 10. The formation of boron trifluoride occurs when boron reacts with: H2O O2 F2 H2SO4 11. What is the primary extraction method for coal? Drilling Open-pit mining Smelting Quarrying 12. Which form of carbon appears as a black, soft, and slippery solid? Diamond Graphite Charcoal Carbon black 13. What is the extraction process for silicon called Carbothermic reduction Smelting Fractional distillation Electrolysis 14. What is the primary reason for the exceptional hardness of diamond? Its layered crystal structure Its ability to form multiple bonds Its unique and symmetrical structure Its tetrahedral arrangement and strong covalent bonds 15. Which allotrope of carbon exhibits electrical conductivity? Diamond Graphite Fullerenes Charcoal 16. What is the stable form of germanium at room temperature? α-Germanium β-Germanium γ-Germanium δ-Germanium 17. Which Group 14 element has the highest catenation ability? Carbon (C) Silicon (Si) Germanium (Ge) Tin (Sn) 18. Which element in Group 14 primarily exhibits an oxidation state of +4? Carbon (C) Silicon (Si) Germanium (Ge) Tin (Sn) 19. Which allotrope of tin is brittle and exhibits non-metallic behavior? White tin Gray tin Red tin Yellow tin 20. What is the primary factor that affects catenation ability? Atomic size Metallic behavior Ionic bonding High electronegativity 21. How do group 15 elements react with oxygen? They form halides They undergo fractional distillation They combine to form phosphoric acid They form oxides 22. What is the primary method of extracting bismuth from lead and copper ores? Smelting Fractional distillation Fractional crystallization Electrolysis 23. What is the oxidation state of arsenic in arsenic pentoxide? +1 +3 +4 +5 24. Group 15 elements react with oxygen to form oxides. Which equation represents the reaction of nitrogen with oxygen to form nitrogen dioxide? N₂ + O₂ → 2NO N₂ + O₂ → 2NO₂ P₄ + 5O₂ → 2P₂O₅ 2Sb + 3O₂ → 2Sb₂O₃ 25. Which Group 15 element is a diatomic gas at room temperature and pressure? Nitrogen Phosphorus Arsenic Antimony 26. Which Group 15 element is commonly used in alloys, such as pewter? Phosphorus Arsenic Antimony Bismuth 27. Which Group 15 element has a pinkish hue when freshly cut but tarnishes to a silvery color upon exposure to air? Phosphorus Arsenic Antimony Bismuth 28. Which hydride compound of Group 15 elements is toxic and flammable? Ammonia (NH₃) Phosphine (PH₃) Arsine (AsH₃) Stibine (SbH₃) 29. Which oxide of Group 15 elements is amphoteric? Nitrogen monoxide (NO) Phosphorus pentoxide (P₂O₅) Arsenic trioxide (As₂O₃) Nitrogen pentoxide (N₂O₅) 30. Which Group 15 hydride acts as a reducing agent and is used in the production of semiconductors? Ammonia (NH₃) Phosphine (PH₃) Arsenic trihydride (AsH₃) Bismuth trihydride (BiH₃) Time's up
