Solve this:

​Q14. Draw a labelled schematic diagram to show the electrolysis of water. Why is the amount of gas collected in one of the test tubes in this activity is double of the amount collected in the other?

Q15. What do you mean by a precipitation reaction?

Q16. A solution of potassium chloride when mixed with silver nitrate solution, an insoluble white substance is formed. Write the chemical reaction involved and also mention the type of the chemical reaction?Solve this:

15. 
When the water vapour rises, they start cooling. The water vapour condenses causing formation of droplets of water. When these droplets become too heavy to float in air , then they come down as precipitation in the form of snow, rain and sleet


16.
When a solution of silver nitrate is mixed with potassium chloride solution, then silver chloride and potassium nitrate are formed. The white insoluble substance (or precipitate) formed in the reaction is nothing but silver chloride. This reaction is an example of double displacement reaction, and occurs almost instantaneously. Following is the chemical equation for the reaction
 

AgNO₃ (aq) + KCl (aq) → AgCl (s) + KNO₃ (aq)

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