Properties of giant covalent structures

• Match the feature of giant covalent structures with its description:

  Structure ↔️ Large networks of atoms

  Bonds ↔️ Strong covalent bonds

  Size ↔️ Extends throughout a solid material

  Unit ↔️ Does not exist as single units
• What type of bonding holds the atoms/molecules together in this crystal lattice?

  • The atoms/molecules are held together by strong intermolecular forces, likely ionic or covalent bonds
• Match the property of diamond with its explanation:

  Hardness ↔️ Strong covalent bonds in 3D network

  High melting point ↔️ Requires breaking many strong bonds

  Poor electrical conductivity ↔️ Valence electrons tightly held
• Diamond is easy to scratch due to its hardness

  False
• How does the structure of graphite differ from the structure of diamond in terms of the hybridization of the carbon atoms?

  In graphite, the carbon atoms are sp2 hybridized, while in diamond they are sp3 hybridized
• Carbon atoms in graphite are arranged in hexagonal patterns within layers.

  True
• What are the two main intermolecular forces holding the layers of carbon atoms together in the graphite structure?

  Van der Waals forces
• Why does diamond have high melting and boiling points?

  Strong covalent bonds
• Graphite conducts electricity because each carbon atom forms only 3 covalent bonds.

  True
• What is the bonding arrangement around each silicon atom in silicon dioxide?

  Tetrahedral
• How are the carbon atoms arranged in the graphite structure?

  • Carbon atoms are arranged in a hexagonal lattice
  • The carbon atoms are connected by covalent bonds
  • The layers of carbon atoms are held together by van der Waals forces
• Match the property of graphite with its application:

  Softness ↔️ Pencils

  Electrical conductivity ↔️ Electrodes

  Lubricant ↔️ Sliding surfaces
• Steps describing the structure of graphite

  1️⃣ Carbon atoms form hexagonal patterns within layers

  2️⃣ Each carbon forms 3 covalent bonds within a layer

  3️⃣ Layers are held together by Van der Waals forces

  4️⃣ Layers can slide past each other
• If you wanted to use graphite as an electrical conductor, which property of its structure would be most important?

  The delocalized electrons in the covalent bonds
• What type of forces allow graphite layers to slide past each other easily?

  Van der Waals forces
• Why does silicon dioxide have a high melting point?

  Strong covalent bonds
• Match the property of silicon dioxide with its explanation:

  High Melting Point ↔️ Requires significant energy to break covalent bonds

  Hardness ↔️ Silicon-oxygen bonds resist deformation

  Electrical Insulation ↔️ Electrons are tightly held within bonds

  Transparency ↔️ Clear lattice enables light transmission
• If the lattice parameter (distance between adjacent atoms/molecules) is $a =$$0.5 \text{ nm}$, what is the volume of the unit cell?


  • Volume of unit cell = $a^3 =$$0.5^3 =$$0.125 \text{ nm}^3$
• Silicon dioxide is transparent because its lattice structure allows light to pass through without significant scattering.

  True
• What type of bonds are found in the structure of diamond?

  Covalent bonds
• Why is graphite a good lubricant?

  The weak van der Waals forces between the layers allow them to slide past each other easily
• What is the shape of the arrangement of carbon atoms in diamond?

  Tetrahedral
• Why does graphite have a high melting point?

  Strong covalent bonds
• Giant covalent structures are composed of single, independent molecules


  False
• What is the structure shown in the image?

  • The structure shown is a crystal lattice
  • It consists of a repeating pattern of atoms or molecules arranged in a 3D grid
• Graphite's structure extends in 2 dimensions, unlike diamond's 3D network.

  True
• How does the arrangement of atoms/molecules in this crystal lattice differ from an amorphous solid?

  In a crystal lattice, the atoms/molecules are arranged in a highly ordered, repeating 3D pattern, while in an amorphous solid they are randomly arranged with no long-range order
• Silicon dioxide has a similar structure to diamond.


  True
• What are two common uses of diamond based on its properties?

  Cutting tools and jewelry
• How many atoms/molecules are present in the unit cell of this crystal lattice?

  9
• What type of structure does silicon dioxide have?

  Giant covalent
• What are the main components of the graphite structure shown in the image?

  • Carbon atoms
  • Van der Waals forces
  • Covalent bonds
• How does the structure of graphite contribute to its properties?

  • The layered structure and weak van der Waals forces allow the layers to slide past each other, making graphite soft and slippery
  • The delocalized electrons in the covalent bonds allow graphite to conduct electricity
  • The strong covalent bonds within the layers make graphite very hard and resistant to compression
• How does the graphite structure differ from the structure of diamond?

  • Graphite has a layered, hexagonal structure, while diamond has a tetrahedral, cubic structure
  • In graphite, the carbon atoms are sp2 hybridized, while in diamond they are sp3 hybridized
  • Graphite has delocalized electrons that allow it to conduct electricity, while diamond is an insulator
• In diamond, each carbon atom forms four tetrahedral bonds with neighboring carbons.

  True
• What are the three-dimensional bonds in silicon dioxide responsible for?

  Stability
• Steps in describing the structure of diamond:

  1️⃣ Carbon atoms form four tetrahedral bonds

  2️⃣ Bonds extend in three dimensions

  3️⃣ Creates a rigid, symmetrical structure

  4️⃣ Every carbon atom is connected to four others
• How many covalent bonds does each carbon atom form in graphite?

  3