Question

Identify the type of chemical reaction in the following statements and define each of them: 

(i) Digestion of food in our body 

(ii) Rusting of iron 

(iii) Heating of manganese dioxide with aluminium powder 

(iv) Blue colour of copper sulphate solution disappears when iron filings are added to it 

(v) Dilute hydrochloric acid is added to sodium hydroxide solution to form sodium chloride and water.

Answer 1

(i) Decomposition Reaction : Carbohydrates are broken down to form glucose. 

(ii) Oxidation Reaction : When an iron object is left in moist air for a considerable time, it gets covered with a red brown flaky substance called rust. 

(iii) Displacement reaction : More reactive metal displaces less reactive metal from its salt solution. 

(iv) Displacement reaction : More reactive metal displaces less reactive metal from its salt solution. 

(v) Double displacement reaction : Reaction in which two compounds react by an exchange of ions to form two new compounds.