What is observed when:

(i) Potassium iodide is added to aqueous lead nitrate?


(ii) Identify the type of reaction.


(iii) Give a balanced chemical equation for this.

(i) When potassium iodide is added to aqueous lead nitrate, it forms potassium nitrate and a precipitate of lead iodide which is yellow in colour.

The reaction that takes place is:


Pb(NO3)2 + 2KI 2PbI + 2KNO3


Note: The insoluble substance formed is known as precipitate.


Precipitate settles down at the bottom of the test tube.


(ii) The type of reaction is double displacement reaction or precipitation reaction.


Any reaction that produces a produces a precipitate can be called a precipitation reaction.


(iii) The balanced chemical equation is:


Pb(NO3)2 + 2KI 2PbI + 2KNO3


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