The d- and f- B...

The main reason for larger number of oxidation states exhibited by the actinoids than the corresponding lanthanoids, is:

Out of $$TiF^{2-}_6$$ and $$CoF^{3-}_6$$ , $$Cu_2Cl_2$$ and $$NiCl^{2-}_4$$ (Z of Ti = 22, Co = 27, Cu = 29, Ni = 28) the colourless species are:

Which one of the following ions is the most stable in aqueous solution?
(At. No. are: $$ Ti = 22, V = 23, Cr = 24, Mn = 25$$)

Which one of the following ions will be colourless in an aqueous solution?

Which ion is colourless?

Which of the following statement is not correct?

Which of the following does not corrode when exposed to the atmosphere?

The number of oxidation states is exhibited by the actinoids more than by the lanthanide. The main reason for this is:

Which of the following shows highest magnetic moment ?

Variable valency is characteristic of: