Q.Write the chemical equation for preparing sodium soap from glyceryl oleate and glyceryl palmitate. Structural formulae of these compounds are given below.

Soaps are prepared by the alkaline hydrolysis of fats and oils, which are esters of glycerol with long-chain fatty acids — this reaction is called saponification. Each glyceryl ester has three ester linkages, so it reacts with 3 molecules of NaOH to give 3 molecules of the sodium salt of the fatty acid (soap) and 1 molecule of glycerol.

• Glyceryl palmitate is the ester of glycerol with palmitic acid ($C_{15}H_{31}COOH$):

  $(C_{15}H_{31}COO)_3C_3H_5 + 3NaOH → 3C_{15}H_{31}COO^-Na^+ + C_3H_5(OH)_3$

  (glyceryl palmitate) + (sodium hydroxide) → (sodium palmitate, a soap) + (glycerol)

• Glyceryl oleate is the ester of glycerol with oleic acid. Oleic acid is an unsaturated (mono-unsaturated) fatty acid with the formula $C_{17}H_{33}COOH$, so its glyceryl triester is $(C_{17}H_{33}COO)_3C_3H_5$: …

Recognise saponification: triglyceride ester + 3 NaOH → 3 sodium salt of fatty acid (soap) + glycerol. Write and balance one equation per given ester, keepin …

• Forgetting the stoichiometric coefficient 3 (a triester needs 3 NaOH and yields 3 soap molecules plus 1 glycerol). …