Chemical Reactions and Equations.
11. The composition of matter changes in a chemical change.
12. Evaporation of water is a physical change.
13. When electric current is passed through acidulated water, electrolysis of water takes place.
14. Addition of an aqueous solution of ZnSO4 to an aqueous solution of BaCl2 is an example of double displacement reaction.
15. The conversion of ferrous sulphate to ferric sulphate is oxidation reaction.
16. Damage of a metal due to oxidation by atmospheric components is called corrosion.
17. The rust chemically is Fe2O3.xH2O.
18. To prevent rusting, a layer of zinc metal is applied on iron sheets.