A polymer is made from compound R, HO-(CH2)4-OH\text{HO-(CH}_2\text{)}_4\text{-OH}HO-(CH2)4-OH, and compound S, HOOC-(CH2)2-COOH\text{HOOC-(CH}_2\text{)}_2\text{-COOH}HOOC-(CH2)2-COOH.
The end groups of adjacent molecules react as the polymer chain grows.
Which statement describes what happens each time a new link forms?
No other molecule is produced as each new link forms.
Water becomes part of the polymer at each new link.
A peptide link forms as the molecules join.
Water is released as each new link forms.
94 exam-style questions on AQA GCSE Chemistry 7.3 Synthetic and naturally occurring polymers, covering 7.3.1 Addition polymerisation, 7.3.2 Condensation polymerisation, 7.3.3 Amino acids, and 7.3.4 DNA (deoxyribonucleic acid) and other naturally occurring polymers. Each one has a worked solution and a mark scheme showing where the marks go.