A researcher models the formation of a polypeptide from several different amino acid molecules. Adding together the formulae of the amino acids predicts more oxygen and hydrogen atoms than are present in the polypeptide.
Explain this difference in the numbers of atoms.
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.