The solution provides answers to questions about the hydrolysis of a triglyceride, preparation of ethyne, and addition polymerization of perspex. What are the original questions?

here are the solutions:

6. (b) (ii) G is completely hydrolysed by heating with aqueous sodium hydroxide.

• (I) Give the structural formula of the alcohol formed. The alcohol formed from the hydrolysis of a triglyceride is glycerol (propane-1,2,3-triol). $$\text{HOCH}_2\text{CH(OH)CH}_2\text{OH}$$
• (II) Write a formula for the sodium salt formed. Assuming compound G is a tri-ester of stearic acid, the sodium salt formed is sodium stearate. $$\text{CH}_3(\text{CH}_2)_{16}\text{COONa}$$
• (III) State the use of the sodium salt. Cleansing agent (soap)

6. (c) Ethyne is the first member of the alkyne family.

• (i) Name two reagents that can be used in the laboratory to prepare the gas.
  • Calcium carbide ($\text{CaC}_2$)
  • Water ($\text{H}_2\text{O}$)
• (ii) Write an equation for the reaction. $$\text{CaC}_2(s) + 2\text{H}_2\text{O}(l) \rightarrow \text{Ca(OH)}_2(aq) + \text{C}_2\text{H}_2(g)$$

6. (d) Perspex is an addition synthetic polymer formed from the monomer,
The monomer is methyl methacrylate: $\text{CH}_2=\text{C}(\text{CH}_3)(\text{COOCH}_3)$.

• (i) What is meant by addition polymerisation? Addition polymerisation is a process where unsaturated monomers (containing double or triple bonds) join together without the loss of any atoms, forming a long chain polymer.

• (ii) Draw three repeat units of Perspex. The repeat unit is $[-\text{CH}_2-\text{C}(\text{CH}_3)(\text{COOCH}_3)-]$. Three repeat units are:

  $$\begin{bmatrix} \text{CH}_3 \\ | \\ -\text{CH}_2-\text{C}- \\ | \\ \text{COOCH}_3 \end{bmatrix} \begin{bmatrix} \text{CH}_3 \\ | \\ -\text{CH}_2-\text{C}- \\ | \\ \text{COOCH}_3 \end{bmatrix} \begin{bmatrix} \text{CH}_3 \\ | \\ -\text{CH}_2-\text{C}- \\ | \\ \text{COOCH}_3 \end{bmatrix}$$

• (iii) Give one use of Perspex. Making lenses (e.g., in spectacles or aircraft windows)

6. (e) State two environmental hazards associated with synthetic polymers.

• Non-biodegradability: Synthetic polymers do not decompose naturally, leading to persistent waste accumulation in landfills and oceans.
• Pollution during incineration: Burning synthetic polymers can release toxic gases and contribute to air pollution.