Note: In the following questions a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.
Assertion : Sodium chloride is added to precipitate soap after saponification.
Reason : Hydrolysis of esters of long chain fatty acids by alkali produces soap in colloidal form.
• The assertion & reason statement states about 2 different reactions.
• The former (assertion) is precipitation whereas the latter is saponification which is basically heating of glyceryl esters (fatty acids with aqueous NaOH soln –
In this reaction esters of fatty acids are hydrolysed & the soap obtained remains in colloidal form.
• Precipitation of this solution is done by addition of NaCl(sodium chloride) which is a different process.