Compound $A$ on borax bead test in reducing flame gives green colour bead. Compound $A$ on treatment with $H_2O_2$ followed by treatment with $Pb(OAc)_2$ gives yellow ppt. The metal ion in the compound $A$ is :

To a solution of a substance,gradual addition of ammonium hydroxide results in a black precipitate which does not dissolve in excess of $NH_4OH$. However,when $HCl$ is added to the original solution,a white precipitate is formed. The solution contained

$H_2S$ gas is passed through an acidified solution containing $Ag^+$,$Cu^{2+}$,and $Zn^{2+}$ ions. Which of these will form a precipitate?

Which of the following compounds will not give a positive chromyl chloride test?

Which ion is precipitated by the reagent $NH_4Cl$ and aqueous $NH_3$?

Which of the following statement$(s)$ is/are correct with reference to $Fe^{2+}$ and $Fe^{3+}$ ions?
$(1)$ $Fe^{3+}$ gives brown colour with potassium ferricyanide
$(2)$ $Fe^{2+}$ gives blue colour with potassium ferricyanide
$(3)$ $Fe^{3+}$ gives red colour with potassium thiocyanate
$(4)$ $Fe^{2+}$ gives brown colour with ammonium thiocyanate