Question

25. Write balanced chemical equations to explain what happens, when
(i) Mercuric oxide is heated.
(ii) Mixture of cuprous oxide and cuprous sulphide is heated.
(iii) Aluminium is reacted with manganese dioxide.
(iv) Ferric oxide is reduced with aluminium.
(v) Zinc carbonate undergoes calcination.​

Answer 1

Answer:

1)2hgo---->2hg+o2

2)2Cu2O + Cu2S ---> 3Cu + SO2.

3)3mno3+4al---->2al2o3+3mn

4)Fe203+2al--->2Fe+Al2

+o3+heat

5)ZnCO3=ZnO+CO2

Answer 2

i) It produces mercury and oxygen.

ii)  It produces copper and sulphur dioxide.

iii) It produces manganese , aluminium oxide and heat.

iv) It produces aluminium oxide, iron and heat.

v)It leads to the production of zinc oxide and carbon dioxide.

Explanation:

Chemical reaction is the symbolic representation of changes which element undergo.