Question

a) Write the essential condition for the following reaction to take place:
2AgBr—-> 2Ag + Br2
Write one application of this reaction.
(b) Complete the following chemical equation of a chemical reaction 2FeS04 —

Answer 1

Answer: a) sunlight

b) $2FeSO_4(s)\rightarrow Fe_2O_3(s)+SO_2(g)+SO_3(g)$

Explanation: a) $2AgBr\rightarrow 2Ag+Br_2$

It is an example of photo decomposition, in which one reactant is converted to two or more than two products by use of light as a source of energy.

It is used in black and white photography due to its sensitivity towards light and used in making Shroud of Turin.

b) This is an example of thermal decomposition  in which one reactant is converted to two or more than two products by use of heat as a source of energy.

Anhydrous white Ferrous sulphate is heated to give reddish brown ferric oxide, sulphur dioxide gas and sulphur trioxide gas.

$2FeSO_4(s)\rightarrow Fe_2O_3(s)+SO_2(g)+SO_3(g)$