Question

Q.9 Assertion (A): Exposure of silver chloride to sunlight for a long duration turns grey due to the formation of silver by decomposition of silver chloride. Reason (R): In this process, sublimation of silver chloride takes place. *​

Answer 1

Answer:

Silver halides, especially Silver chloride undergo decomposition in presence of sunlight to produce silver metal and a halogen gas (chlorine or bromine gas). White color of silver chloride changes to grey due to formation of silver metal. Therefore, the option A is correct.

Answer 2

Only the Assertion (A) is true and Reason (R) is false.

Explanation:

• A decomposition reaction can be defined as the process in which a reactant is broken into two or more distinct products.
• Silver chloride undergoes a process called decomposition during the presence of sunlight and forms a silver metal and a halogen gas.
• During decomposition, the white colour of silver chloride changes into grey forming a silver metal.

The decomposition reaction is given below:

$2AgCl\;\xrightarrow{Sunlight}\;2Ag\;+\;Cl_2$

From this reaction, we can infer that silver chloride is a photosensitive compound.