Question

What is the action of heat on ${\mathrm{K}}_2{\mathrm{Cr}}_2{\mathrm{O}}_7$?

Answer 1

Action of heat on ${\mathrm{K}}_2{\mathrm{Cr}}_2{\mathrm{O}}_7$

• On heating Potassium dichromate $\left({\mathrm{K}}_2{\mathrm{Cr}}_2{\mathrm{O}}_7\right)$​, the formation of Potassium chromate $\left({\mathrm{K}}_2{\mathrm{CrO}}_4\right)$, and chromic oxide $\left({\mathrm{Cr}}_2{\mathrm{O}}_3\right)$ with the evolution of oxygen $\left({\mathrm{O}}_2\right)$ gas takes place.
• The reaction is as follows:-

$4{\mathrm{K}}_2{\mathrm{Cr}}_2{\mathrm{O}}_7\left(\mathrm{s}\right)\stackrel{∆}{\to }4{\mathrm{K}}_2{\mathrm{CrO}}_4\left(\mathrm{s}\right)+2{\mathrm{Cr}}_2{\mathrm{O}}_3\left(\mathrm{s}\right)+3{\mathrm{O}}_2\left(\mathrm{g}\right)$