How many of the following show variable oxidation states in their compounds?
Sc,Cr,Cu,Zn,Fe,Hg,La

Oxidation state of Fe in compound (F) is

Fe shows an oxidation state of +1 in

Fe shows an oxidation state of +1 in :

How does manganese show its variable oxidation states?

Fe show on oxidation state of +1 in:

Fe show on oxidation state of +1 in:

How many of the following elements show +2 as their most stable oxidation state ? Sc, Sn, Zn, Be, Pb, Co, Ag, Ti, Fe

How many of the following elements show +2 as their most stable oxidation state ? Sc, Sn, Zn, Be, Pb, Co, Ag, Ti, Fe