A pink coloured salt turns blue on heating. The presence of which cation is most likely ?
$Co^{2+}$
$Cu^{2+}$
$Zn^{2+}$
$Fe^{2+}$
The number of $d-$ electrons in $F{e^{2 + }}$ (at no. of $Fe = 26$) is not equal to that of the
White silver surface turns black when $O_3$ is passed over it. This is due to the formation of
When $KMnO_4$ solution is added to hot oxalic acid solution, the decolourisation is slow in the beginning but becomes instantaneous after some time. This is because
Predict which of the following will be coloured in aqueous solution? $Ti ^{3+}, V ^{3+}, Cu ^{+},$ $Sc ^{3+}, Mn ^{2+}, Fe ^{3+}$ and $Co ^{2+} .$ Give reasons for each.
Percentage of silver in German silver is