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• Ionic bonds


  Bonds which form between metals and non-metals
• Covalent bonds


  Bonds which form between non-metals
• Reactivity of metals


  Different metals have different reactivities. This is shown using an activity (or reactivity) series.
• Activity (or reactivity) series

  • Li
  • K
  • Na
  • Ca
  • Mg
  • Al
  • Mn
  • Cr
  • Zn
  • Fe
  • Ni
  • Sn
  • Pb
  • H
  • Cu
  • Hg
  • Ag
  • Au
  • Pt
• Covalent compounds


  Prefixes are used to name compounds, so CCI, is known as carbon tetrachloride.
• Determining formula for covalent compounds

  The valency of each atom needs to be considered.
• Naming ionic compounds


  The metal component forms the first part of the name and the non-metal forms the second part of the name. The ending of the non-metal is changed to -ide.
• Determining formula for ionic compounds


  The electrovalencies need to be used to determine the number of each ion required to give an overall neutral charge.
• Periodic table


  • Shows all discovered elements in order of their atomic number or number of protons
  • Because atoms are electrically neutral, the number of protons in an atom is the same as the number of electrons
  • The mass number of an atom is the sum of the number of protons and neutrons in the atom (the particles within the nucleus of the atom)
• Groups


  Columns in the periodic table. Elements in similar groups have similar physical and chemical properties.
• Types of elements in the periodic table

  • Metals
  • Metalloids
  • Non-metals
• Metals


  • Towards the left of the periodic table, mostly solid at room temperature, good conductors, malleable, lustrous and ductile
• Non-metals


  • Towards the right of the periodic table, dull, brittle and poor conductors. Many non-metals are gases.
• Metalloids


  • Found between metals and non-metals on the periodic table and have properties of both metals and non-metals
• Electron shell diagram


  A simplified model of an atom, showing electrons arranged in a series of energy levels around the nucleus known as shells
• Maximum number of electrons in each shell

  Can be calculated using the rule 2n², where n is the number of the shell
• Electron configuration


  The arrangement of electrons for each element, e.g. sodium is written as 2,8,1
• Ionic bonding


  Occurs between metals and non-metals, in which metals give up electrons to non-metals
• Cations


  Positively charged ions formed when metal atoms lose electrons
• Anions


  Negatively charged ions formed when non-metal atoms gain electrons
• Ionic compounds


  • Usually solid at room temperature, with high melting points, brittle when a force is applied, can dissolve to form aqueous solutions and conduct electricity when aqueous
• Covalent bonding


  Occurs between non-metals, in which they share electrons to gain full outer shells
• Bonding pairs


  Electrons that are shared in covalent bonds
• Non-bonding pairs/lone pairs


  Electrons that are not shared in covalent bonds
• Named families of elements

  • Alkali metals
  • Alkaline earth metals
  • Pnictogens
  • Chalcogens
  • Halogens
  • Noble gases
  • Transition metals
  • Lanthanoides
  • Actinoides
• Alkali metals


  • Very reactive metals in group 1 of the periodic table
• Alkaline earth metals


  • Reactive metals in group 2 of the periodic table
• Halogens


  • Non-metal elements in group 17 of the periodic table
• Noble gases


  • Elements in the last column of the periodic table that are unreactive
• Transition metal block


  • A block of metallic elements in the middle of the periodic table
• Patterns in the periodic table

  • Atomic number and mass number
  • Atomic radius
  • Melting points
  • Reactivity
  • Metallic character
• As you move down a group, more electrons, protons and neutrons are present. The electrons are positioned in electron shells. Elements in the same period have the same number of electron shells.
• As you move across a period, the number of electrons and protons increases. The number of shells remains the same. The increase of negatively charged electrons and positively charged protons across the group means a stronger attraction exists between the shell and the nucleus, causing the atomic radius to decrease.
• Aqueous solutions


  Solutions in which water is the solvent
• Covalent bonding occurs between non-metal atoms to form molecules such as water (H₂O) and carbon dioxide (CO2), and large network lattices such as diamond (C) and quartz (SiO₂).
• Ionic compounds


  • They are usually solids at room temperature
  • They normally have very high melting points because the electrostatic force of attraction between the ions is very strong
  • They are brittle as when a force is applied to the lattice the ions with like charges align and actively repel each other, shattering the lattice
• Aqueous solutions normally conduct electricity
• Covalent bond


  A shared pair of electrons holding two atoms together
• Covalent bonding occurs between non-metal atoms to form molecules such as water (H₂O) and carbon dioxide (CO2), and large network lattices such as diamond (C) and quartz (SiO₂)
• Molecules can be made of more than one type of atom or made of atoms of the same element