A chemist is identifying two compounds, P and Q. Each compound contains carbon and hydrogen atoms only, and its five carbon atoms form one unbranched chain. The table shows the number of bonds between carbon atoms in one molecule of each compound.
| Compound | Number of carbon–carbon single covalent bonds | Number of carbon–carbon double covalent bonds |
|---|---|---|
| P | 4 | 0 |
| Q | 3 | 1 |
Calculate the molecular formula of P and the molecular formula of Q.
A model of a third compound, R, is made by adding one carbon atom to an end of Q's carbon chain. The new carbon atom is joined to the chain by a single covalent bond. All the original carbon–carbon bonds in Q remain unchanged.
Predict the molecular formula of R. Explain your answer.
122 exam-style questions on OCR GCSE Chemistry 2.3 Properties of materials, covering 2.3.1 Carbon bonding and the variety of organic compounds, 2.3.2 Diamond, graphite, fullerenes and graphene, 2.3.3 Bond strength, changes of state and predicting states, 2.3.4 Bulk properties and types of bonding, and 2.3.5 Nanoparticles: scale, surface area, uses and risks. Each one has a worked solution and a mark scheme showing where the marks go.