Polylactic acid (PLA) is a biodegradable thermoplastic aliphatic polyester derived from renewable resources, such as corn starch, and is widely manufactured to mitigate the global environmental impact of conventional petroleum-based plastics. Which functional group linkage is formed in the backbone of the polymer during the condensation polymerisation of its monomer, lactic acid (2-hydroxypropanoic acid)?
−CONH−-\text{CONH}-−CONH−
−COO−-\text{COO}-−COO−
−O−-\text{O}-−O−
−CH2−CH2−-\text{CH}_2-\text{CH}_2-−CH2−CH2−
83 exam-style questions on OCR GCSE Chemistry Organic chemistry. Each one has a worked solution and a mark scheme showing where the marks go.