Transition metals

• Transition metals


  Located in the periodic table between group 2 and group 3. 'Transition' means 'in-between'
• Transition metals


  • Over 30 transition metals
• Typical metals


  The transition metals are known as 'typical' metals
• The transition metals are known as 'typical' metals because of their physical properties
• Physical properties of transition metals

  • Lustrous (bright and shiny)
  • High density
  • Good conductors of heat and electricity
  • High melting and boiling points (except mercury)
  • Hard and strong
  • Malleable (can be bent and pressed into different shapes)
  • Ductile (can be drawn into wires)
• Reactivity of transition metals

  Much less reactive than alkali metals, tend to react relatively slowly with air, water (except iron) and acid
• The general trend is for reduced reactivity across periods, with exceptions such as zinc being more reactive than might be expected
• Transition metal ions


  • All transition metals lose electrons when they react, and so form positive ions
  • Most transition metals can form more than one type of ion, they have variable valency
  • Some transition metals only make one type of ion, e.g. silver only forms Ag+ ions, zinc only forms Zn2+ ions
• Coloured compounds of transition metals

  Most transition metals form coloured compounds, e.g. copper(II) compounds are blue, iron(II) compounds are usually green, iron(III) compounds are usually orange/brown
• Uses of coloured transition metal compounds

  • Coloured glazes on pottery
  • Colouring paints
  • Colouring stained glass windows
  • Colouring gemstones
• Complex ions


  A complex ion has a metal ion at its centre with a number of other molecules or ions surrounding it, attached by coordinate (dative covalent) bonds
• Examples of complex ions formed by transition metals


  • [Fe(H2O)6]2+
  • [Co(NH3)6]2+
  • [Cr(OH)6]3-
  • [CuCl4]2-
• Catalytic activity of transition metals

  Transition metals and their compounds are often good catalysts, either due to their ability to change oxidation state or to adsorb and activate other substances on their surface
• Examples of transition metal catalysts


  • Iron in the Haber Process
  • Nickel in the production of margarine
  • Vanadium(V) oxide in the Contact Process
  • Platinum in catalytic converters
  • Titanium in the production of plastics
• Catalyst


  A substance that speeds up a chemical reaction without being used up
• Alloys


  Transition metals are often mixed with other metals or non-metals to form alloys, changing the properties of the metal to be better suited for a particular purpose