The elements of 3d transition series are given as:Sc, Ti, V, Cr, Mn, Fe, Co
Answer the following:
(i) Write the element which shows maximum number of oxidation states. Give reason.

(ii) Which element has the highest m.p.?
(iii) Which element shows only +3 oxidation state?
(iv) Which element is a strong oxidising agent in +3 oxidation state and why?

(i) Cr and Mn shows maximum number (six) of oxidation states as they have maximum number (five) of unpaired electrons in 3d orbital.
(ii) Chromium has the highest m.p as it has maximum number of unpaired electrons and form stronger metallic bonds.
(iii) Scandium shows only +3 oxidation state.
(iv) Iron is a strong oxidizing agent in +3 oxidation state.
It readily accepts an electron to form +2 oxidation state.
Iron in +3 oxidation state can also accept 3 electrons for 0 oxidation state.