Answer:
Chlorine gas is produced
Step-by-step explanation:
One of the methods of laboratory preparation of chlorine gas is to heat manganese dioxide with concentrated hydrochloric acid. The acid is oxidized by the manganese dioxide to liberate chlorine gas as follows;
MnO2(s) + 4HCl(aq) -------> MnCl2(aq) + 2H2O(l) + Cl2(g)
Hence, When manganese dioxide is heated with concentrated hydrochloric
acid, chlorine gas is liberated.