Question

The black compound which on heating with concentrated Hydrochloric acid gives a greenish yellow gas

Answer 1

Question#47284 – Chemistry – Inorganic Chemistry

Question:

The black compound which on heating with concentrated Hydrochloric acid gives a greenish yellow gas

Answer:

Greenish yellow gas is probably Cl₂. It is released as the result of oxidation half-reaction:

$$2 \mathrm{Cl}^{-} - 2 \mathrm{e}^{-} \rightarrow \mathrm{Cl}_{2}$$

The black compound is a black MnO₂ oxide. The equation of redox reaction:

$$\mathrm{MnO}_{2} + 4 \mathrm{HCl} \rightarrow \mathrm{MnCl}_{2} + \mathrm{Cl}_{2} + 2 \mathrm{H}_{2}\mathrm{O}$$