A chemist checks proposed repeating units for polymers P and Q.
| Polymer | Monomer | Other product formed | Proposed repeating unit |
|---|---|---|---|
| P | CH2=C(CH3)2\text{CH}_2{=}\text{C}(\text{CH}_3)_2CH2=C(CH3)2 | None | [-CH2-C(CH3)2-]n\left[\text{-CH}_2\text{-C}(\text{CH}_3)_2\text{-}\right]_n[-CH2-C(CH3)2-]n |
| Q | H2N-CH(CH3)-COOH\text{H}_2\text{N-CH}(\text{CH}_3)\text{-COOH}H2N-CH(CH3)-COOH | Water | [-NH2-CH(CH3)-COOH-]n\left[\text{-NH}_2\text{-CH}(\text{CH}_3)\text{-COOH-}\right]_n[-NH2-CH(CH3)-COOH-]n |
Explain whether each proposed repeating unit is correct. Give a corrected repeating unit for any proposal that is incorrect.
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.