bonding, structure + properties of matter

• What are ions made from?

  Electrons being transferred
• What are ions?

  Charged particles, single or groups of atoms
• Why do atoms become ions?

  To achieve a full outer shell
• What happens when metals form ions?

  They lose electrons, forming positive ions
• What happens when non-metals form ions?

  They gain electrons, forming negative ions
• What determines the charge on an ion?

  The number of electrons lost or gained
• What is ionic bonding?

  The transfer of electrons between atoms
• What occurs when a non-metal and a metal react?

  The metal loses an electron, non-metal gains
• What attracts oppositely charged ions in ionic bonding?

  Electrostatic forces
• What do dot and cross diagrams represent?

  The arrangement of electrons in bonding
• What do dot and cross diagrams not show?

  Structure, size, or arrangement
• What structure do ionic compounds form?

  A giant ionic lattice
• How are ions arranged in a giant ionic lattice?

  Closely packed regular lattice
• What is a property of ionic compounds?

  High melting and boiling points
• Why do ionic compounds have high melting and boiling points?

  Strong bonds between ions require energy to break
• Why can't solid ionic compounds conduct electricity?

  Ions are held in place and cannot move
• When can ionic compounds conduct electricity?

  When molten or dissolved in water
• What is a covalent bond?

  Sharing pairs of electrons between non-metals
• What is a simple molecular substance?

  Molecules with a few atoms joined by covalent bonds
• What holds simple molecular substances together?

  Strong covalent bonds, weak intermolecular forces
• What is required to melt or boil simple molecular substances?

  Breaking weak intermolecular forces
• What state are most molecular substances at room temperature?

  Gases or liquids
• How do molecular substances change with size?

  Forces of attraction increase as molecules get bigger
• Why do simple molecular substances not conduct electricity?

  They lack charged particles
• What are polymers?

  Long chains of repeating units
• How are atoms in a polymer joined?

  By strong covalent bonds
• What type of forces do polymers have?

  Strong intermolecular forces
• What state are most polymers at room temperature?

  Solid
• What are giant covalent structures?

  Macromolecules with strong covalent bonds
• What are the melting and boiling points of giant covalent structures?

  Very high melting and boiling points
• Why do giant covalent structures not conduct electricity?

  They lack charged particles
• What are allotropes?

  Different structural forms of the same element
• What is diamond's structure and properties?

  Hard, giant covalent structure, high melting point
• What is graphite's structure?

  Sheets of hexagons with weak interlayer bonds
• How does graphite conduct electricity?

  Delocalised electrons allow conductivity
• What is graphene?

  One layer of graphite with strong covalent bonds
• What is metallic bonding?

  Involves delocalised electrons in metals
• What holds metals together?

  Electrostatic attraction between metal ions
• What state are most metals at room temperature?

  Solid
• What are the properties of metals?

  Good conductors of heat and electricity