Give one example each of a chemical reaction characterised by:

(i) evolution of a gas


(ii) change in colour


(iii) formation of a precipitate


(iv) change in temperature


(v) change in state.

(i) Reaction between zinc metal and sulphuric acid.

(ii) Reaction between citric acid and purple colored potassium permanganate. (from purple to colorless).


(iii) Reaction between Potassium iodide and lead nitrate is characterized by the formation of a yellow precipitate of lead iodide.


(iv) The reaction between quick lime and water to form slaked lime is characterized by a change in temperature.


(v) Water and carbon dioxide are formed when wax is burned. Wax is solid whereas products are liquid and gas.


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