C2 - bonding, structure, and properties of matter

• What type of bond do non-metals form when they share electrons?


  Covalent bonds
• What is the result of non-metals joining together by covalent bonds?


  They achieve full outer shells of electrons
• What are examples of simple molecular substances?


  Chlorine and ammonia
• What are giant covalent structures made of?


  Large numbers of non-metal atoms bonded covalently
• What is the difference between simple molecular substances and giant covalent structures?


  Simple molecular substances consist of small molecules, while giant covalent structures consist of large networks of atoms
• Why do simple molecular substances have low melting and boiling points?


  Because only weak intermolecular forces need to be broken
• At what temperature does chlorine boil?


  • 34 degrees Celsius
• How does the size of molecules affect their boiling points in halogens?


  Larger molecules have more intermolecular forces, leading to higher boiling points
• What is the boiling point of bromine?


  59 degrees Celsius
• What is the boiling point of iodine?


  184 degrees Celsius
• Why don't simple molecular substances conduct electricity?


  Because they have no free electrons or charged particles
• What are the properties of giant covalent structures?


  They are very strong and have high melting and boiling points
• What is silicon dioxide also known as?


  Silica
• What is the main component of sand?

  Silicon dioxide
• What are the key differences between simple molecular substances and giant covalent structures?


  • Simple molecular substances:
  • Small molecules
  • Weak intermolecular forces
  • Low melting and boiling points
  • Do not conduct electricity

  
  

  • Giant covalent structures:
  • Large networks of atoms
  • Strong covalent bonds
  • High melting and boiling points
  • Generally do not conduct electricity (except graphite)
• How do the properties of giant covalent structures relate to their bonding and structure?


  They are strong and have high melting points due to strong covalent bonds in a repeating lattice structure
• What is the significance of recognizing giant covalent structures?


  It helps in understanding their properties and behaviors in different conditions
• What are the three important examples of giant covalent structures?


  • Diamond
  • Graphite
  • Silicon dioxide
• Why do atoms form ions?


  Atoms form ions to achieve a full outer shell for stability.
• What is an example of a single atom ion?


  Na⁺ (sodium ion)
• What is an example of a group of atoms that forms an ion?


  Hydroxide ion (OH^-)
• What does the group number in the periodic table indicate?


  The group number indicates how many electrons are in the outermost shell of the atoms.
• What type of ions do group two elements form?

  Group two elements form two plus ions.
• What type of ions do group seven elements form?


  Group seven elements gain one electron to become one minus ions.
• How can we represent the gain or loss of electrons in chemical equations?


  We can write equations showing the atom forming an ion and the electrons involved.
• How would you write the equation for chlorine forming a chloride ion?


  Cl + e^- → Cl^-
• How would you write the equation for magnesium forming a magnesium ion?

  Mg → Mg²⁺ + 2e^-
• How would you write the equation for oxygen forming an oxide ion?


  O + 2e^- → O^2-
• What is the process of ion formation in relation to stability?


  • Atoms gain or lose electrons.
  • They aim for a full outer shell.
  • This process increases their stability.
• What type of bond is formed when particles bond together through ionic bonds?


  Ionic bonds
• How does a sodium atom become a sodium ion?


  A sodium atom loses one electron to form a sodium one plus ion
• Why does a sodium atom need to lose an electron?


  To achieve stability by having a full outer shell
• What does chlorine need to do to form a chloride ion?


  Chlorine needs to gain one electron
• What happens to sodium and chlorine after the transfer of electrons?


  Both become ions with full outer shells of electrons
• How are the charges of ions represented in diagrams?


  With big square brackets around them and their charge in the top right corner
• What is the nature of the attraction between oppositely charged ions?


  They are attracted to each other by electrostatic forces
• What is the strength of an ionic bond compared to covalent bonds?


  Similar in strength
• What is a dot and cross diagram used for?


  To represent the bonding of atoms and the movement of electrons
• What should you show to indicate the movement of electrons in a dot and cross diagram?


  With an arrow
• When drawing a dot and cross diagram, what shells should you include?

  All electron shells or just the outermost shell, depending on instructions