Delhi 2014) Answer: The variability of oxidation state of transition elements is due to incompletely filled d-orbitals and presence of unpaired electrons, i.e. These elements show variable oxidation state because their valence electrons in two different sets of orbitals, that is (n-1)d and ns. Except scandium, the most common oxidation state shown by the elements of first transition series is +2. There is a great variety of oxidation states but patterns can be found. These elements show variable oxidation state because their valence electrons in two different sets of orbitals, that is (n-1)d and ns. Why do transition metals have variable oxidation states? The transition elements have outer electrons that occupy a very large shell. Their general electronic configuration is: where n is the outermost shell. Oxidation states, (aka oxidation numbers), are numbers that show how many electrons the element would lose or gain if it were to bond to other atoms. Thus, transition elements have variable oxidation states. (Comptt. The 4s electrons are first used and then 3d electrons. (i) Name the element showing maximum number of oxidation states among the first… The variable oxidation states shown by the transition elements are due to the participation of outer ns and inner (n–1)d-electrons in bonding. pH has an effect on the redox potential of the reduction of transition metal ions from higher to lower oxidation states. (ns) and (n -1) d electrons have … The valence electrons of these elements enter d-orbital. • maximum oxidation state rises across the group to manganese • maximum falls as the energy required to remove more electrons becomes very high • all (except scandium) have an M2+ ion This is a table that shows each element's outermost electron shell configuration. Solution for (a) Why do transition elements show variable oxidation states? Why do transition elements show variable oxidation states? Manganate (VII) ions, MnO₄⁻, are strong oxidising agents in acidic solution but a weaker oxidising agent in alkaline solution. (i) Name the element showing maximum number of oxidation states among the first series of transition metals from Sc (Z = 21) to Zn (Z = 30). For example: manganese shows all the oxidation states from +2 to +7 in its compounds. Reason: Close similarity in energy of 4s and 3d electrons. Oxidation state of an element is defined as the degree of oxidation (loss of electron) of the element in achemical compound. Transition elements exhibit a wide variety of oxidation states in their compounds. Properties All transition metals except Sc are capable of bivalency. (ii) Name the element which shows only +3 oxidation state. The energy difference between these orbitals is very less, so both the energy levels can be used for bond formation. This oxidation state arises from the loss of two 4s electrons. Why do transition elements show variable oxidation states? Transition elements are the elements which lie between 's' and 'p' block elements. i know that-arises from the similar energies required for removal of 4s and 3d electrons.