Covalent Bonding

• Sharing electron

  • non-metals bond together and they share pairs of electrons to make a covalent bonds
  • positively charged nuclei of the bonded atoms are attracted to the shared pair of electrons by electrostatic forces making covalent bonds very strong
  • atoms only share electrons in their outer shells
  • each single covalent bond provides one extra shared electron for each atom
• sharing electrons

  • each atom involved makes enough covalent bonds to fill up its outer shell
  • having a full outer shell gives them the electronic structure of a noble gas which is very stable
  • this bonding only with non-metal elements and compounds non-metals
• Drawing covalent bonds

  • dot and cross diagrams to show the bonding in covalent compounds 
  • Electrons drawn in the overlap between the outer orbitals of two atoms are shared between those atom
  • useful for showing which atoms the electrons in a covalent bond come from
  • they don't show the relative sizes of the atoms, or how the atoms are arranged in space
• Drawing covalent bonds

  • The 3D model of ammonia shows the atoms, the covalent bonds and their arrangement in space next to each other
  • 3D models can quickly get confusing for large molecules where there are lots of atoms to include
  • They don't show where the electrons in the bonds have come from, either
  • molecular formula of a simple molecular compound from any of these diagram by counting up how many atoms of each element there are.