Which of the following compounds is metallic and ferromagnetic ?
$VO_2$
$MnO_2$
$TiO_2$
$CrO_2$
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 $MCl_3$
The spin-only magnetic moment value of the compound with strongest oxidizing ability among $MnF _{4}, MnF _{3}$ and $MnF _{2}$ is $.............$ $B.M.$ [nearest integer]
The addition of metals like $Cr,\,Mn,\,W$ and $Ni$ to ordinary steel makes it
The metal commonly present in brass and german silver is