$A$ solution prepared in conc. $HCl$ sometimes gives white turbidity even in the absence of $1^{st}$ group,when water is added to it. It is due to the presence of

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:

Sodium carbonate cannot be used in place of ammonium carbonate for the precipitation of the fifth group radicals because

Compound $X$ is tested and the results are shown in the table.

Test	Result
Aqueous $NaOH$ is added, then heated gently.	Gas given off which turns damp red litmus paper blue.
Dilute $HCl$ is added.	Effervescence, gas given off which turns lime water milky and acidified $K_2Cr_2O_7$ paper green.

Which ions are present in compound $X$?

$A$ colorless aqueous solution contains nitrates of two metals,$X$ and $Y$. When it was added to an aqueous solution of $NaCl$,a white precipitate was formed. This precipitate was found to be partly soluble in hot water to give a residue $P$ and a solution $Q$. The residue $P$ was soluble in aqueous $NH_3$ and also in excess sodium thiosulfate. The hot solution $Q$ gave a yellow precipitate with $KI$. The metals $X$ and $Y$,respectively,are

In the wet tests for identification of various cations by precipitation,which transition element cation does not belong to group $IV$ in qualitative inorganic analysis?