Answer the case-based question given below.
 
When electricity is passed through an aqueous solution of sodium chloride (called brine), it decomposes to form sodium hydroxide. 
 
a. Write the chemical equation involved in this process. 

b. What substances are formed at the cathode in the alkali process?
 
c. What are the uses of the gas liberated at anode?
 
 
d. What are the main products of the given process?