Question

Manganese$\left(IV\right)$oxide, lead$\left(IV\right)$oxide, and red lead$\left({\mathrm{Pb}}_3{\mathrm{O}}_4\right)$ react with concentrated hydrochloric acid liberating chlorine.
What kind of compound can be added to bleaching powder to obtain chlorine?

Answer 1

1. Dilute Hydrochloric acid is added to bleaching powder to obtain chlorine.
2. Bleaching powder liberates chlorine gas when reacted with an access supply of dilute hydrochloric acid.
3. $\underset{\mathrm{Bleaching}\mathrm{Powder}}{{\mathrm{CaOCl}}_2\left(\mathrm{s}\right)}+\underset{\mathrm{dil}\mathrm{Hydrochloric}\mathrm{acid}}{2\mathrm{HCl}\left(\mathrm{aq}\right)}\to \underset{\mathrm{Calcium}\mathrm{chloride}}{{\mathrm{CaCl}}_2\left(\mathrm{s}\right)}+{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)+\underset{\mathrm{Chlorine}\mathrm{Gas}}{{\mathrm{Cl}}_2\left(\mathrm{g}\right)}$