(i) Define TFM value.
(ii) Differentiate thermoplastic and thermosetting.

Explanation

(i) 1. The quality of a soap is described in terms of total fatty matter (TFM value). It is defined as the total amount of fatty matter that can be separated from a sample after spliting with mineral acids. Higher the TFM value in the soap, better is its quality.
2. As per BIS standards, Grade I soaps should have 76% minimum TFM value
(ii) Difference between thermoplastic and thermosetting :
`{:("No.","Thermoplastic","Thermosetting"),(i.,"They do not soften on heating and harden on ","They do not soften on heating and they"),(,"cooling, and they can be remoulded.","cannot be remoulded."),(ii.,"They consists of linear long chain polymers","The consist of three dimensional network structure"),(,"and low molecular weights polymers.","and high molecular weight polymers."),(iii.,"All the polymer chains are held together by","All the polymer chains are linked"),(,"weak Vanderwaals forces.","by strong covalent."),(iv.,"They are weak, soft and less brittle","They are strong, hard and more brittle."),(v.,"They are formed by addition","They are formed by condensation"),(,"Polymerisation.","polymerisation."),(vi.,"They are soluble in organic solvents.","They are insoluble in organic solvents."),(vii.,"Example : PVC, polythene, polystrene etc.","Example : Bakelite, melamine etc."):}`