Who do soaps not work in hard water?

Name some important categories of food additives.

Give some of the advantages of using food additives.

Write a short note on Antioxidants.

How is Low density polyethene prepared?

Give the structure of melamine formaldehyde resin.

The monomer is capro lactam   Identify the polymer when the monomer is heated at 533K.

How is Nylon - 6,6 prepared? Give it use.

Give the condensation reaction between urea and formaldehyde. Identify the polymer.

Write the preparation of neoprene and give its use.

How is Buna - N prepared? Give its use.

Identify the polymer and write the reaction involved.
(i) Buta-1,3-diene and styrene in the presence of sodium.
(ii) 3 - hydroxy butanoic acid and 3-hydroxy pentanoic acid.

Give examples for
(i) addition polymer,
(ii) Synthetic rubbers,
(iii) Condensation polymers,
(iv) formaldehyde resins.

Identify the monomers of the following polymers.

(ii) (NH(CH₂)₆ NHCO (CH₂)₄ CO)n
(iii) \({ CH }_{ 2 }-\underset { \overset { | }{ Cl } }{ C } =CH-{ CH }_{ 2 })_{ n }\)

State any three advantages of food additives.