Pair of ions which gives blue colour in aqueous state :
$V^{+4},\,Ni^{+2},\, Ti^{+3}, \,Co^{+2}, \,Fe^{+3}, \,Cu^{+2}$
$V^{+4},\, Cu^{+2}$
$Co^{+2}, \,Ni^{+2}$
$Fe^{+3},\, Ti^{+3}$
$Cr^{+3}, \,Zn^{+2}$
Which has the maximum ferromagnetic character
Incorrect match is
ppt $\rightarrow$ colour
Which one of the following does not correctly represent the order of property indicated against it
Which of the following is not true for transition metals
The catalyst used in the contact process is