MnO2(s)+4HCl(aq)→MnCl2(aq)+Cl2(g)+2H2O(l)
Identify the oxidising and reducing agents in the above reaction. Give an example of a decomposition reaction. [3 MARKS]
Each point: 1 Mark
1. MnO2 loses oxygen, therefore it is reduced, and thus it acts as an oxidizing agent.
2. HCl loses hydrogen. It itself is oxidized, thus it acts as a reducing agent.
Therefore, in the reaction MnO2 is oxidizing agent and HCl is reducing agent.
3. Example of a decomposition reaction: Calcium carbonate decomposes on heating and forms calcium oxide and carbon dioxide.
CaCO3Heat−−→CaO+CO2