The number of statement$(s)$ correct from the following for copper (atomic number $29$) is/are $...$
$(A) \ Cu(II)$ complexes are always paramagnetic
$(B) \ Cu(I)$ complexes are generally colourless
$(C) \ Cu(I)$ is easily oxidized
$(D)$ In Fehling solution,the active reagent has $Cu(II)$

Statement $(I)$ $Co^{2+}$ has a higher magnetic moment than $Cr^{3+}$.
Statement $(II)$ Ionisation enthalpies of $Ce$,$Pr$ and $Nd$ are higher than $Th$,$Pa$ and $U$.
Which of the following is correct?

Which of the following is not arranged in the correct sequence?

The transition metals have a less tendency to form ions due to

Given below are two statements:
Statement $I$: The number of pairs among $[Ti^{4+}, V^{2+}], [V^{2+}, Mn^{2+}], [Mn^{2+}, Fe^{3+}]$ and $[V^{2+}, Cr^{2+}]$ in which both ions are coloured is $3$.
Statement $II$: The number of pairs among $[La^{3+}, Yb^{2+}], [Lu^{3+}, Ce^{4+}]$ and $[Ac^{3+}, Lr^{3+}]$ ions in which both are diamagnetic is $3$.
In the light of the above statements,choose the correct option from the options given below:

Which of the following statements are correct?
$(i)$ $V^{2+}$ liberates hydrogen from a dilute acid.
$(ii)$ The earlier members of the lanthanide series behave more like aluminium.
$(iii)$ The 'silver' $UK$ coins are made of $Cu/Ni$ alloy.
$(iv)$ The maximum oxidation state exhibited by Neptunium is $+7$.