Discussion Forum

In the following reaction sequence in aqueous  solution, the species X, Y and Z, respectively are

$S_{2}O_3^{2-}\underrightarrow {Ag^{+}}$  $X (Clear. solution)$   $\underrightarrow {Ag^{+}}$  $Y (white. ppt)\underrightarrow {with.time}$  $Z (black.ppt)$

Answer:

Explanation:

$2S_{2}O_3^{2-}+Ag^{+}\rightarrow [Ag (S_{2}O_{3})_{2}]^{3-} (Clear.solution)$

$[Ag(S_{2}O_{3})_{2}]^{3-}+3Ag^{+}\rightarrow 2 Ag_{2}S_{2}O_{3}( white.ppt)$

$Ag_{2}S_{2}O_{3}+H_{2}O\rightarrow Ag_{2}S(Black .ppt)+H_{2}SO_{4}$