Question

How do you prepare Hydrogen sulfide$\left({\mathrm{H}}_2\mathrm{S}\right)$?

Answer 1

Hydrogen sulfide$\left({\mathrm{H}}_2\mathrm{S}\right)$

• Hydrogen sulfide (${\mathrm{H}}_2\mathrm{S}$) is colorless, highly corrosive, flammable, and poisonous, with the repellant odour of rotten eggs.
• It can be prepared by heating one part of sulfur and two parts of paraffin wax above $160°\mathrm{C}$.
• The rate of reaction is proportional to temperature and this reaction is fast and accurate.
• $$\begin{gathered} {\mathrm{C}}_{\mathrm{x}}{\mathrm{H}}_{\mathrm{y}}+\mathrm{S}\stackrel{160°\mathrm{C}}{\to }{\mathrm{H}}_2\mathrm{S}+{\mathrm{C}}_{\mathrm{x}}{\mathrm{H}}_{\mathrm{z}}\mathrm{where}\mathrm{z}=\mathrm{y}-2 \\ \mathrm{Paraffin} \end{gathered}$$.
• The reaction mixture must not be heated above $200°\mathrm{C}$, because a lot of paraffin vapor will clog the tubes.
• Hydrogen sulfide$\left({\mathrm{H}}_2\mathrm{S}\right)$ can also be produced when the broken pieces of Iron sulfide$\left(\mathrm{FeS}\right)$ put in Kipp’s apparatus come in contact with dilute Hydrochloric acid or Sulfuric acid.$\underset{\mathrm{Iron}\mathrm{sulfide}}{\mathrm{FeS}\left(\mathrm{s}\right)}+\underset{\mathrm{Sulphuric}\mathrm{acid}}{{\mathrm{H}}_2{\mathrm{SO}}_4\left(\mathrm{aq}\right)}\to \underset{\mathrm{Iron}\mathrm{sulphate}}{{\mathrm{FeSO}}_4\left(\mathrm{aq}\right)}+\underset{\mathrm{Hydrogen}\mathrm{sulphide}}{{\mathrm{H}}_2\mathrm{S}\left(\mathrm{g}\right)}$