Essential Chemistry for IGCSE - Structure And Bonding (Section 5)

  • 1
    What type of bond is present in a molecule of carbon dioxide (CO2)?
    پاسخ دهید
    (B)
    Covalent
  • 2
    What is the chemical formula for sodium chloride?
    پاسخ دهید
    (B)
    NaCl
  • 3
    What type of bond would you expect to find in a molecule of hydrogen chloride (HCl)?
    پاسخ دهید
    (B)
    Covalent
  • 4
    In which of the following compounds are covalent bonds present?
    پاسخ دهید
    (C)
    Methane
  • 5
    Which of the following allotropes of carbon conducts electricity?
    پاسخ دهید
    (B)
    Graphite
  • 6
    What is typically the state of simple molecular substances at room temperature?
    پاسخ دهید
    (D)
    Any of the above
  • 7
    Which of the following correctly represents the bonding in magnesium oxide (MgO)?
    پاسخ دهید
    (B)
    Mg transferring electrons to O.
  • 8
    Which statement best describes the formation of an ionic bond?
    پاسخ دهید
    (B)
    The attraction between a positive ion and a negative ion.
  • 9
    In graphite, why are the layers able to slide over each other?
    پاسخ دهید
    (C)
    Because of weak intermolecular forces.
  • 10
    What type of bonding is present in silicon dioxide?
    پاسخ دهید
    (B)
    Covalent
  • 11
    Why is graphite suitable for use as an electrode?
    پاسخ دهید
    (B)
    Because it has delocalised electrons and conducts electricity.
  • 12
    What type of bonding is present in hydrogen molecules (H₂)?
    پاسخ دهید
    (C)
    Covalent
  • 13
    In a covalent bond, the atoms are held together by...
    پاسخ دهید
    (A)
    Shared electrons
  • 14
    Which of the following is formed when an atom gains electrons?
    پاسخ دهید
    (B)
    An anion
  • 15
    Which of the following describes the process of forming an ion?
    پاسخ دهید
    (B)
    The gain or loss of an electron.
  • 16
    Which of the following are not examples of giant covalent structures?
    پاسخ دهید
    (D)
    Water
  • 17
    Which of the following properties is typically associated with simple molecular substances?
    پاسخ دهید
    (C)
    Low melting point.
  • 18
    Which of the following statements correctly describes the octet rule?
    پاسخ دهید
    (B)
    Atoms tend to gain, lose, or share electrons to achieve a full outer shell of 8 electrons.
  • 19
    Which of the following is a property of a simple molecular compound?
    پاسخ دهید
    (D)
    Low melting point.
  • 20
    Which compound conducts electricity when dissolved in water?
    پاسخ دهید
    (C)
    Sodium chloride
  • 21
    What are the two main types of particles present in an ionic compound?
    پاسخ دهید
    (B)
    Positive ions (cations) and negative ions (anions).
  • 22
    In graphite, what type of forces hold the layers together?
    پاسخ دهید
    (C)
    Van der Waals forces
  • 23
    Which of the following compounds is most likely to have high melting and boiling points?
    پاسخ دهید
    (B)
    Sodium chloride (NaCl)
  • 24
    Why does graphite conduct electricity?
    پاسخ دهید
    (B)
    It contains delocalised electrons
  • 25
    What structure does silicon dioxide (SiO2) have?
    پاسخ دهید
    (C)
    Giant covalent structure
  • 26
    Which of the following is not a property of ionic compounds?
    پاسخ دهید
    (C)
    Dissolve in organic solvents
  • 27
    What causes graphite to be soft?
    پاسخ دهید
    (C)
    Weak intermolecular forces between layers.
  • 28
    Why does diamond have a high melting point?
    پاسخ دهید
    (B)
    It has strong covalent bonds throughout its structure
  • 29
    Which of the following is a giant covalent structure?
    پاسخ دهید
    (C)
    Silicon dioxide
  • 30
    What is the electronic configuration of chlorine (atomic number 17)?
    پاسخ دهید
    (C)
    2, 8, 7
  • 31
    What is the maximum number of electrons that can occupy the outermost shell of an atom?
    پاسخ دهید
    (C)
    8
  • 32
    What type of bond is formed between atoms with very different electronegativity values?
    پاسخ دهید
    (C)
    Ionic bond
  • 33
    How many covalent bonds are formed in a molecule of water (H₂O)?
    پاسخ دهید
    (B)
    Two
  • 34
    Which of the following is a feature of simple molecular substances?
    پاسخ دهید
    (C)
    Low melting and boiling points.
  • 35
    What is the formula for the compound formed between sodium and chlorine?
    پاسخ دهید
    (C)
    NaCl
  • 36
    In covalent bonding, what is the role of the nuclei of the atoms?
    پاسخ دهید
    (A)
    They attract the shared electrons.
  • 37
    Why does graphite have a high melting point?
    پاسخ دهید
    (A)
    Because it is made of strong covalent bonds within the layers
  • 38
    What is the state of matter that allows ionic compounds to conduct electricity?
    پاسخ دهید
    (D)
    Aqueous solution or molten state
  • 39
    What is a covalent bond made up of?
    پاسخ دهید
    (A)
    Shared electrons
  • 40
    Why does silicon dioxide have a high melting point?
    پاسخ دهید
    (B)
    Because it has a giant covalent structure with strong bonds.
  • 41
    Which of the following statements is true about the formation of ions?
    پاسخ دهید
    (C)
    Cations are positively charged, formed by losing electrons.
  • 42
    What is the charge on a sodium ion after it forms an ionic bond?
    پاسخ دهید
    (A)
    +1
  • 43
    Which of the following best explains why graphite can conduct electricity?
    پاسخ دهید
    (A)
    Graphite has delocalised electrons
  • 44
    What type of structure does silicon dioxide (SiO2) have?
    پاسخ دهید
    (A)
    Giant covalent
  • 45
    What type of bond results from the transfer of electrons?
    پاسخ دهید
    (B)
    Ionic
  • 46
    What is the electronic configuration of oxygen (atomic number 8)?
    پاسخ دهید
    (B)
    2, 6
  • 47
    What type of structure does carbon dioxide (CO2) have?
    پاسخ دهید
    (B)
    Simple molecular
  • 48
    Which structure describes the bonding in silicon dioxide (SiO2)?
    پاسخ دهید
    (C)
    Giant covalent structure
  • 49
    What type of structure do both diamond and silicon dioxide have?
    پاسخ دهید
    (A)
    Giant covalent structure
  • 50
    Which of the following are correct regarding the properties of graphite?
    پاسخ دهید
    A
    B