During the mass spectrometry analysis of a hydrolyzed protein sample, a biochemist isolates a pure sample of an acidic amino acid. This amino acid can be represented by the general structural formula:
H2N−[R]−COOH \text{H}_2\text{N} - \text{[R]} - \text{COOH} H2N−[R]−COOHwhere [R]\text{[R]}[R] represents the variable central section of the molecule.
The relative formula mass (MrM_rMr) of this amino acid is 147.
Calculate the relative formula mass of the section represented by [R]\text{[R]}[R].
Relative atomic masses (ArA_rAr):
H=1C=12N=14O=16 \text{H} = 1 \quad \text{C} = 12 \quad \text{N} = 14 \quad \text{O} = 16 H=1C=12N=14O=165 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 (HT only), 7.3.3 Amino acids (HT only), 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.