Assign $A, B, C, D$ from the given type of reaction.
$MCrO_4 \downarrow (M^{2+} = Ba^{2+}, Pb^{2+}) + AcOH \longrightarrow$ No dissolution

Which metal ion gives a violet bead in the borax bead test?

$A$ chemistry student trying to detect the metallic ion in a salt,makes a paste on a clean platinum wire loop of the salt with concentrated $HCl$. When he takes a small amount of this paste and keeps it in a non-luminous Bunsen flame,the colour of the flame changes to grassy green. He should,therefore,conclude that the metal is

While preparing crystals of Mohr's salt,dil. $H_2SO_4$ is added to a mixture of ferrous sulphate and ammonium sulphate,before dissolving this mixture in water,dil. $H_2SO_4$ is added here to:

Starch paper is used to test for the presence of

When sodium chloride is heated with concentrated $H_2SO_4$ and solid potassium dichromate,which compound containing $Cr$ in the $+6$ oxidation state is formed as a gas?