The solution of $BiCl_{3}$ in dil. $HCl$ when diluted with water,forms a white precipitate which is:

Which reagent is used to test for the presence of the $Fe^{+2}$ ion?

Which of the following pairs cannot be distinguished by passing $H_2S$ gas?

Consider the following reactions:
$X(aq.) \xrightarrow{K_4[Fe(CN)_6]}$ Chocolate brown ppt.
$X(aq.) \xrightarrow{AgNO_3}$ White ppt. (insoluble in dil. $HNO_3$)
Then $X$ will be:

In qualitative analysis,in order to detect $II$ group basic radicals,$H_2S$ gas is passed in the presence of dilute $HCl$ to:

When $H_2S$ gas is passed through a hot acidic aqueous solution containing $Al^{3+}$,$Cu^{2+}$,$Pb^{2+}$ and $Ni^{2+}$,a precipitate is formed,which consists of