A) 10% B) 50% C) 80.1% D) 19.9%
A) 10B B) 17B C) 11B D) 7B
A) 19.9 s B) 3.5×10−10 s C) 3.5×10−22 s D) 80.1 s
A) Superconductivity B) Proton emission C) Nuclear halo D) Alpha decay
A) 3 B) 1 C) 3/2 D) 1/2
A) 11B B) 7B C) 17B D) 10B
A) γ-orthorhombic B) β-tetragonal C) α-rhombohedral D) β-rhombohedral
A) Six B) Three C) Five D) Four
A) 2200–2500 °C B) 1800–2200 °C C) 1500–1800 °C D) 100–500 °C
A) Above 160 GPa B) 50–80 GPa C) 12–20 GPa D) 1–5 GPa
A) Above 100 K B) Between 20–30 K C) Below 6–12 K D) Exactly 0 K
A) Borax B) Sassolite C) Carbon D) Tincal
A) Iron B) Potassium C) Oxygen D) Carbon
A) Tincal B) Sal sedativum C) Boracium D) Sassolite
A) 300 AD B) 700 AD C) 1600 AD D) 1808 AD
A) Ezekiel Weintraub B) Jabir ibn Hayyan C) Georgius Agricola D) Sir Humphry Davy
A) Marco Polo B) Georgius Agricola C) Francis Marion Smith D) Jöns Jacob Berzelius
A) Preservative B) Flux C) Catalyst D) Glaze
A) 1808 B) 1824 C) 1777 D) 1909
A) Tincal B) Boracium C) Sassolite D) Sal sedativum
A) Sassolite B) Boracium C) Tincal D) Borax
A) 1909 B) 1808 C) 1827 D) 1872
A) Francis Marion Smith B) Jöns Jacob Berzelius C) Sir Humphry Davy D) Ezekiel Weintraub
A) Sassolite B) Tincal C) Boracium D) Boron
A) Iron B) Potassium C) Copper D) Gold
A) Davy and Berzelius B) Agricola and Marco Polo C) Smith and Weintraub D) Gay-Lussac and Thénard
A) Sir Humphry Davy B) Ezekiel Weintraub C) Louis Jacques Thénard D) Jöns Jacob Berzelius
A) Joseph Louis Gay-Lussac B) Ezekiel Weintraub C) Sir Humphry Davy D) Jöns Jacob Berzelius
A) Sassolite B) Boric acid C) Borax D) Sal sedativum
A) Brown powder B) Clear crystal C) White gas D) Silvery liquid
A) Cosmic ray spallation B) Stellar nucleosynthesis C) Radioactive decay D) Photosynthesis
A) 1 percent B) 0.1 percent C) 0.001 percent D) 0.01 percent
A) China B) Russia C) Turkey D) USA
A) Food preservative B) Additive in fiberglass C) Water purification D) Fuel additive
A) Brighter color B) Lower cost C) Better electrical insulation D) Greater thermal shock resistance
A) Boron-12 B) Boron-5 C) Boron-10 D) Boron-15
A) Nutritional B) Toxic C) Neutral D) Beneficial
A) Meteoroids B) Atmospheric air C) Ocean water D) Human blood
A) As a fertilizer B) As a lubricant C) As a bleach D) As a semiconductor
A) Noble gas B) Metalloid C) Halogen D) Alkali metal
A) Silicon B) Aluminum C) Boron D) Carbon
A) It has more electrons in the p-orbital B) It has a larger atomic radius C) It reflects its electropositive character D) It forms stable covalent networks
A) It is too abundant to be valuable B) It is highly radioactive C) The pure material is extremely difficult to prepare D) It reacts instantly with all known substances
A) Decomposition of diborane at high temperatures B) Zone melting of volcanic ash C) Reaction of boron halides with nitrogen D) Reduction of boric oxide with magnesium
A) It turns into liquid B) It reacts with nitrogen to form nitrides C) It immediately combusts D) A protective oxide or hydroxide layer forms
A) Boric acid B) Borane C) Boron nitride D) Boron trioxide
A) Carbon B) Silicon C) Aluminum D) Magnesium
A) II B) III C) I D) IV
A) Silicon B) Aluminium C) Nitrogen D) Carbon
A) Boron spheres B) Boron chains C) Boron icosahedra D) Boron cubes
A) From pure elemental boron B) From diborane decomposition C) From borates D) From boron halides
A) The Aufbau principle B) The octet rule C) Hund's rule D) The Pauli exclusion principle
A) B2X6 B) BX3 C) BX2 D) BX4
A) Planar trigonal B) Octahedral C) Tetrahedral D) Linear
A) Strongly alkaline B) Lewis acidic C) Neutral D) Lewis basic
A) Fluoroboride B) Trifluoroborate C) Tetrafluoroborate D) Borate
A) Petrochemical B) Pharmaceutical C) Food processing D) Textile
A) BCl3 B) BF3 C) BBr3 D) B2F4
A) B4H10 B) B7Br7 C) B2Cl6 D) B3F9
A) Pentaborate anions B) Tetraborate anions C) Triborate anions D) Monoborate anions
A) Potassium B) Sodium C) Magnesium D) Calcium
A) B-B bonds B) B-O-B bonds C) B-C bonds D) B-H bonds
A) R2BOH B) B(OR)3 C) BX3 D) B(OH)3
A) E.J. Corey B) Akira Suzuki C) Linus Pauling D) Herbert C. Brown
A) Electrolysis B) Acid-base reaction C) Oxidation D) Carbothermic reduction |