Chemical bonds: Ionic covalent and metallic

• How many types of chemical bonds are there

  3
• What are the types of chemical bonds

  ionic

  covalent

  metallic
• Ionic bonds are between a metal and non-metal
• When and iconic bond occurs the metal will lose electrons and become positively charged while the non-metal gains electrons and becomes negatively charged
• An iconic compound is a compound that only contains ionic bonds
• Ionic compounds have regular structures called giant iconic lattice structures.

  They have strong electrostatic attraction between oppositely charged ions
• Ionic compounds have

  -high melting and boiling points

  -cannot conduct electricity when solid but can when melted
• Types of strong chemical bonds

  • Ionic
  • Covalent
  • Metallic
• Ionic bonds


  • Bonds between a metal and a non-metal
  • Atoms react to gain a full outer shell
  • Metal atom loses electrons and forms a positively charged ion
  • Non-metal gains electrons to fill its outer shell and forms a negatively charged ion
  • Oppositely charged ions are strongly attracted by electrostatic forces
• Showing an ionic bond with a dot and cross diagram

  Positive and negative ion attracted to each other
• Ionic compound


  A compound that only contains ionic bonds
• Properties of ionic compounds

  • Have regular structures called a giant ionic lattice
  • Held together by strong electrostatic forces of attraction between oppositely charged ions
  • Have high melting and boiling points
  • When solid, ions are held strongly in place and can't conduct electricity
  • When molten or dissolved, electrons are free to move and can carry a charge
• Covalent bonding


  1. Two non-metals share electrons to gain full outer shells

  2. Shared electrons are strongly attracted to the positive nuclei

  3. Electrons are only shared in the outer shell

  4. Each covalent bond provides one shared electron

  5. Atoms involved fill up their outer shell, giving it the structure of a noble gas

  
• Substances with covalent bonds

  • Usually have simple molecular structures
  • Atoms in the molecules are held together by very strong covalent bonds
  • Forces of attraction between the molecules is weak, so melting and boiling points are very low
• Drawing covalent bonds with dot and cross diagrams

  Electrons in the overlap of the two atoms are shared

  
• Displayed formula


  Shows the relative size of the atoms and how they are arranged, but not where the electrons have come from
• Metallic bonding


  • Giant structure of positive metal ions in a regular structure, held together by delocalised, negative electrons
  • Extremely strong electrostatic force of attraction between the positive ions and shared negative electrons
  • Delocalised electrons give metals interesting properties: being solid at room temperature, good conductors, and malleable
• what’s an alloy

  A mixture of two or more metals, harder than pure metals as different sized metals distort the layers which makes it harder for them to move over each other