The metal that does not give the borax bead test is

Identify the statement which is not correct regarding copper$(II)$ sulphate.

$MnO_2$ when fused with $KOH$ and oxidised in air gives a dark green compound $X$. In acidic solution,$X$ undergoes disproportionation to give an intense purple compound $Y$ and $MnO_2$. The compounds $X$ and $Y$,respectively,are

The yellow colour of chromates changes to orange on acidification due to the formation of:

Oxidation states of the metal in the minerals haematite and magnetite,respectively,are

When $MnO_2$ is fused with $KOH$,a coloured compound is formed. The product and its colour are: