Which is most reactive metal
$Fe$
$Pt$
$Ni$
$Co$
Which one of the following statements shows the correct percentage of carbon in steel, pig iron and wrought iron
Properties common to the elements manganese, iron, cobalt, nickel and copper include the ready formation by them all of
$(I)$ coloured ions in aqueous solution
$(II)$ oxides of nitrogen are formed on reaction with concentrated $HNO_3$
$(III)$ chlorides of formula $MCl_2$ and $MCl_3$
Amongst $TiF_6^{2-}$ , $CoF_6^{3-}$ , $Cu_2Cl_2$ and $NiCl_4^{2-}$ the colourless species are
Which of the following is more paramagnetic
The stability of $Cu ^{2+}$ is more than $Cu ^{+}$salts in aqueous solution due to -