D-block elements

• Where are the d-block elements located?

  between group 2 and group 13 of the periodic table

  across the periodic table from scandium to zinc, the 3d sub-shell has the highest energy electrons - hence the name
• What are the properties of the d-block elements?

  all metallic and so display the typical physical properties of metals.

  They have high melting and boiling points and are shiny in appearance and conduct both electricity and heat. Their metallic properties give rise to some of their uses.
• What are d-block elements used for?

  elements such as copper, silver and nickel have been used in coinage

  iron is used extensively in construction and the production of tools

  copper is used in electrical cables and water pipes

  titanium is known for its strength and is used in the aerospace industry as well as in medical applications such as joint replacement and in cosmetic dentistry
• scandium electron configuration?

  1s22s22p63s23p63d14s2 or [Ar]3d14s2
• titanium electron configuration?

  1s22s22p63s23p63d24s2 or [Ar]3s24d2
• Why are copper and chromium special?

  Their electron configuration so not follow the expected principle for placing electrons singly in orbitals before pairing. A half-filled d5 sub-shell and a fully filled d10 sub-shell give additional stability to atoms of chromium and copper
• When the d-block elements scandium to zinc form positive ions from their atoms, they lose their 4s electrons before losing and of the 3d electrons
• When forming an atom, the 4s orbital fills before the 3d orbitals

  When forming an ion, the 4s orbitals empties before the 3d orbitals
• What is the definition of a transition element?

  d-clock elements that form at least one ion with a partially filled d-orbital
• Why are scandium and zinc not classed as transition metals?

  They do not match the definition despite being d-block elements

  Scandium only forms the Sc3+ ion by loss of 2 4s electrons and 1 3d electron

  Sc: 1s22s2p63s23p63d14s2

  Sc3+: 1s22s22p63s33p6

  Zinc only forms the Zn2+ ion by the loss of its 2 4s electrons

  Zn: 1s22s22p63s23p63d104s2

  Zn2+: 1s22s22p63s23p63d10

  Sc3+ ions have empty d-orbitals and Zn 2+ have full d-orbitals
• What are the properties of the transition metals and their compounds?

  1. they form compounds in which the transition element has different oxidation states
  2. they form coloured compounds
  3. the elements and their compounds can act as catalysts
• Variable oxidation states:

  Transition elements form compounds with more than one oxidation state e.g. iron forms 2 chlorides - iron (II) chloride, FeCl2 and iron (III) chloride, FeCl3
• Does the number of oxidation states increase across the transition elements?

  Yes to manganese, then decreases.

  All transition metals form compounds with an oxidation number of +2, resulting from the loss of 2 electrons
• V+2

  light purple
• Cr+2

  light blue
• Mn+2


  pale pink
• Fe+2


  pale green
• Co+2


  pink
• Ni+2


  green
• Ti+3

  pale purple
• V+3

  green
• Cr+3


  green
• Fe+3


  pale yellow
• Co+3


  green
• Cu+3


  light blue
• V+4

  light blue
• Mn+4

  purple
• V+5

  yellow
• Cr+6

  orange
• Mn+6


  green
• Mn+7


  pale purple
• potassium dichromate (VI)


  bright orange
• cobalt (II) chloride

  pink-purple
• nickel (II) sulfate

  green
• hydrated copper (II) sulfate

  blue
• What is the colour of a solution linked to?

  The partially filled d-orbitals of the transition metal ion. The colour of a solution can vary with different oxidation states.
• Common oxidation states of iron?

  +2 and +3 in its compounds

  iron (II): Fe2+ - 1s22s22p63s23p63d6 - pale green

  iron (III): Fe3+ - 1s22s22p63s23p63d5 - yellow
• Common oxidation states of chromium?

  +3 and +6 in its compounds

  Cr(III) - green

  Cr (VI) - yellow or orange