Zinc and Scandium are not transition elements! Transition elements are d block elements that have an ion with an incomplete d subshell. Element Electronic Configuration Sc 1s22s22p63s23p6 4s23d1 Ti 1s22s22p63s23p6 4s23d2 V 1s22s22p63s23p6 4s23d3 Cr 1s22s22p63s23p6 4s13d5 Mn 1s22s22p63s23p6 4s23d5 Fe 1s22s22p63s23p6 4s23d6 Co 1s22s22p63s23p6 4s23d7 Ni 1s22s22p63s23p6 4s23d8 Cu 1s22s22p63s23p6 4s13d10 Zn 1s22s22p63s23p6 4s23d10 Zinc and Scandium are not transition elements! Scandium forms only one ion, Sc3+. In forming this ion, scandium loses the two electrons in the 4s subshell and the one electron in the 3d subshell. This leaves the ion with no d subshell – it therefore isn’t a transition metal. Zinc forms only one ion, Zn2+. In forming this ion, zinc loses the two electrons in the 4s subshell. This leaves the ion with a complete d subshell – it therefore isn’t a transition metal. Note that chromium and copper don’t fit the pattern. They fill their 3d subshell before their 4s subshell.

Transition Metals have variable Oxidation States Fe3+ + e- Fe2+ Pale green  Yellow Oxidation States of Manganese +2 in Mn2+ +3 in Mn2O3 +4 in MnO2 +6 in MnO42- +7 in MnO4- Cr2O72- + 6H+ + 6e- 2Cr3+ + 7H2O Orange  Green MnO4- + 8H+ + 5e- Mn2+ + 4H2O Purple  Pale Pink Precipitation reactions of Transition Metals Catalytic Activity Metal Ion & Colour Precipitate Cu2+ - Blue Solution Cu(OH)2 -Blue Co2+ - Pink Solution Co(OH)2 -Blue Fe2+- Pale Green Solution Fe(OH)2 - Green Fe3+ - Yellow Solution Fe(OH)3 - Brown Iron in the Haber Process: combines hydrogen and nitrogen to make ammonia Nickel in the hydrogenation of C=C bonds: manufacture of margarine from vegetable oils. Vanadium(V) oxide in the Contact Process: reaction which converts sulphur dioxide into sulphur trioxide. Sulphur dioxide gas is passed together with air (as a source of oxygen) over a solid vanadium(V) oxide catalyst. Manganese (IV) Oxide in the decomposition of hydrogen peroxide N2 + 3H2  2NH3 CH2= CH2 + H2 CH3CH3 3. 2SO2 + O2  2SO3 4. H2O2  H2O + ½ O2