Question

Write an activity to observe silver bromide decomposes in the presence of sunlight. 

(OR) 

Write an activity for photochemical reaction.

Answer 1

• Take some quantity of silver bromide on a watch glass. 
• When we observe the colour of silver bromide it is light yellow in colour. 
• Place the watch glass in sunlight for sometime. 
• Silver bromide decomposes to silver and bromine in sunlight. 
• After sometime we observe that the colour of silver bromide changes into grey colour.   
• Light yellow coloured AgBr changes into Ag and Br. 
• This decomposition reaction occurs in the presence of sunlight and such reactions are called photochemical reactions. 
• The above decomposition reactions require some energy to convert reactants to products. 
• This type of reactions are called endothermic reactions.
• Equation :