Chemistry of the d-block transition metals

Chemistry of the d-block transition metals

General Characteristics of d-block Transition Metals

  • Transition metals are known as d-block elements, as their last electron enters the d-orbital.
  • These metals demonstrate a range of oxidation states due to the availability of both 4s and 3d electrons in bonding.
  • They have high melting and boiling points as a result of strong metallic bonding.
  • They are known for their high density and hardness and exhibit magnetic properties.
  • Many are good conductors of heat and electricity due to delocalised electrons.

Colour and Coordination Compounds

  • Transition metals and their compounds often exhibit vibrant colours, which are a result of d-d electron transitions.
  • They form complex ions with ligands which donate a pair of electrons to the central metal atom to form a coordinate bond. Compounds of this type are called coordination compounds.
  • They can form both octahedral and tetrahedral complexes; the shape depends on the size and charge of the ligands.
  • Examples include [Fe(H2O)6]2+ and [CuCl4]2-.

Redox Reactions and Catalytic Activity

  • The variable oxidation states allow transition metals to undergo redox reactions which are reactions involving reduction (gain of electrons) and oxidation (loss of electrons).
  • Catalysts lower the activation energy of a reaction and speed up the reaction rate. Transition metals and their compounds often act as catalysts, both in the industry and in the body.
  • The catalytic activity is attributable to their ability to change oxidation state.

Reaction with Water and Acids

  • Transition metals typically do not react with water or acids as readily as alkali metals do.
  • However, some exceptions exist. For example, chromium and manganese react with acids to produce hydrogen gas and the corresponding salts.

Remember to focus on understanding the key concepts and properties of d-block transition metals, including their unique physical traits, reactivity, and behaviour in various chemical reactions.