During the qualitative analysis of $SO_{3}^{2-}$ using dilute $H_{2}SO_{4}$,$SO_{2}$ gas is evolved which turns $K_{2}Cr_{2}O_{7}$ solution (acidified with dilute $H_{2}SO_{4}$):

Which of the statement is incorrect for the given paragraph?
Simple salt $\xrightarrow{\text{Flame test}}$ Golden yellow flame
Simple salt $\xrightarrow[MnO_2]{Conc. H_2SO_4} (X)$ Yellowish green gas
Simple salt $\xrightarrow{AgNO_3} (Z)$ White ppt. (Insoluble in dil. $HNO_3$)
Simple salt $\xrightarrow[Conc. H_2SO_4]{K_2Cr_2O_7} (Y)$ Reddish brown vapour

In the brown ring test,the brown color for $NO_2^-$ and $NO_3^-$ is due to the formation of which complex ion?

$[X] + H_2SO_4 \to [Y]$ (a colourless gas with irritating smell).
$[Y] + K_2Cr_2O_7 + H_2SO_4 \to$ green solution.
$[X]$ and $[Y]$ are:

$[X] +$ dil. $H_{2}SO_{4} \longrightarrow [Y]:$
Colourless,suffocating gas
$[Y] + K_{2}Cr_{2}O_{7} + H_{2}SO_{4} \longrightarrow$
Green colouration of solution
Then,$[X]$ and $[Y]$ are

To an inorganic mixture,dilute $H_2SO_4$ is added in the cold; a colourless,odourless gas is evolved. The mixture contains: