Phenol and fomaldehyde undergo condensation to give a polymar (A) which on heating with formaldehyde gives a thermosetting polymer (B) Name the polymers. Write the reaction involved in the formation of (A) what is the structural difference between two polymers?

Explanation

Phenol and formaldehyde undergo condensation to give a polymer novolac (A) which on heating with formaldehde gives bakelite(B) as a thermosetting polymer
Sequenc of the reaction can be written as

Structural difference in between these two is that novolac is a linear polymer while bakelite is a cross linked polymer.