Transition elements are coloured.

Write down the electronic configuration of:
$(i) Cr^{3+}$
$(ii) Pm^{3+}$
$(iii) Cu^{+}$
$(iv) Ce^{4+}$
$(v) Co^{2+}$
$(vi) Lu^{2+}$
$(vii) Mn^{2+}$
$(viii) Th^{4+}$

An element of the $3d-$ transition series shows two oxidation states $x$ and $y$,which differ by two units. Then:

Which of the following metal ions in their respective oxidation states forms a coloured compound?

Besides $Zn$ and $Cu$,german silver contains the metal

The electronic configuration of $Ag$ atom is