Consider the following reactions (unbalanced) \[ \begin{aligned} & \mathrm{Zn}+\text{ hot conc. } \mathrm{H}_{2}\mathrm{SO}_{4} \rightarrow \mathrm{G}+\mathrm{R}+\mathrm{X} \\ & \mathrm{Zn}+\text{ conc. } \mathrm{NaOH} \rightarrow \mathrm{T}+\mathrm{Q} \\ & \mathrm{G}+\mathrm{H}_{2}\mathrm{S}+\mathrm{NH}_{4}\mathrm{OH} \rightarrow \mathrm{Z} \text{ (a precipitate) }+\mathrm{X}+\mathrm{Y} \end{aligned} \] Choose the correct option(s).

(B) Bond order of Q is 1 in its ground state; (C) Z is dirty white in colour; (D) R is a V-shaped molecule

(A) The oxidation state of Zn in T is +1

JEE Advanced · 2019 · 27 May 2019 · Paper 2 · General Principles and Processes of Isolation of Metals

Consider the following reactions (unbalanced)

Zn + hot conc. H_{2} SO_{4} \to G + R + X Zn + conc. NaOH \to T + Q G + H_{2} S + NH_{4} OH \to Z (a precipitate) + X + Y

Choose the correct option(s).

Answer: (B), (C), (D)

The balanced reactions are:

$Zn + 2 H_{2} SO_{4}$ (hot, conc.) $\to ZnSO_{4}$ (G) $+ SO_{2}$ (R) $+ 2 H_{2} O$ (X)

$ZnSO_{4} + H_{2} S + 2 NH_{4} OH \to ZnS$ (Z) $+ 2 H_{2} O + (NH_{4})_{2} SO_{4}$ (Y)

Correct answers: (2), (3), (4).

JEE Advanced · 2019 · 27 May 2019 · Paper 2 · One or more correct options