The metal that has a very low melting point and whose periodic position is close to a metalloid is:

Which of the following is a colourless ion?

Cerium $(IV)$ has a noble gas configuration. Which of the following is the correct statement about it?

Which of the following properties is not characteristic of transition metals?

Match the species in List-$I$ with their correct electronic configuration in List-$II$.

List-$I$	List-$II$
$(1) \ \text{Cr}$	$(A) \ [\text{Ar}] \ 3d^8 4s^0$
$(2) \ \text{Fe}^{2+}$	$(B) \ [\text{Ar}] \ 3d^{10} 4s^1$
$(3) \ \text{Ni}^{2+}$	$(C) \ [\text{Ar}] \ 3d^6 4s^0$
$(4) \ \text{Cu}$	$(D) \ [\text{Ar}] \ 3d^5 4s^1$
	$(E) \ [\text{Ar}] \ 3d^6 4s^2$

For $Cr, Mn, Fe,$ and $Co$,the $E_{{M^{3+}}/{M^{2+}}}^{\circ}$ values are $0.41, +1.57, +0.77,$ and $+1.97 \ V$ respectively. Which of these metals is most easily oxidized from the $+2$ to the $+3$ oxidation state?