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 $Cu(II)$

Which of the following transition metals is used as a catalyst?

Identify the correct option:
$(I)\ AgCl$ is not soluble in $H_2O$ but soluble in $KCN$.
$(II)\ Zn$ when reacts with cold v.v. dil $HNO_3$ gives $NH_4NO_3$.
$(III)\ CuSO_4$ reacts with $KI$ to form $Cu_2I_2 + K_2SO_4$.
$(IV)\ CuSO_4 \cdot 5H_2O \xrightarrow{1000\,^oC}$ The gases liberated are $SO_2$ and $O_2$.

Which of the comparison regarding $Zn, Cd, Hg$ is/are incorrect?
$(I)$ $ZnCl_2$ is ionic whereas $CdCl_2$ and $HgCl_2$ are covalent
$(II)$ $Zn$ and $Cd$ dissolve in dilute acid $(HCl)$ liberating $H_2$ but $Hg$ cannot
$(III)$ $Zn$ and $Cd$ form white ppt. of $Zn(OH)_2$ and $Cd(OH)_2$ but $Hg$ forms coloured ppt. of $HgO$ or $Hg(OH)_2$
$(IV)$ All form $M_2^{2+}$ type ion

The difference in the 'spin-only' magnetic moment values of $KMnO_4$ and the manganese product formed during titration of $KMnO_4$ against oxalic acid in acidic medium is .................... $BM$. (nearest integer)

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 $+7$.