Question

Write an activity for the formation of lead iodide and potassium nitrate. 

(OR) 

Your friend has a doubt about chemical double displacement reaction. How can you clarify his/her doubt by showing an experiment? Explain.

 (OR)

What happens if lead nitrate solution is added to potassium iodide solution? Explain the activity.

Answer 1

It forms yellow precipitate of lead iodide. 

1. Take a pinch of lead nitrate and dissolve in 5.0 ml of distilled water in a test tube. 

2. Take a pinch of potassium iodide in another test tube and dissolve in distilled water. 

3. Mix lead nitrate solution with potassium iodide solution.

4. We observe that a yellow coloured substance which is insoluble in water, is formed. 

5. This insoluble substance is known as precipitate. 

6. The precipitate is Lead Iodide.

7. Equation : Fb(NO₃)_2(aq) + 2 KI_(aq) → Pbl_2(s) + 2KNO_3(aq)

8. In the above reaction, lead ion and potassium ion exchange their places each other. 

9. Lead ion combines with iodide ion and forms Pbl₂ as precipitate and  KNO₃ remains in the solution. 

10. Such reaction is double displacement reaction.