A local magician was showing magic in a village street. He took egg shell and poured a solution over it. As a result, effervescence were formed. When he took a burning matchstick over it, it went off :
(a) Identify the solution poured and the substance present in egg shell.
(b) What is the reason behind effervescence ?
(c) Write its balanced chemical equation.
(d) Give the common name of the substance present in the egg shell.