A researcher is preparing particles for a laboratory investigation.
A cube-shaped particle has a side length of 4 μm4\ \mathrm{\mu m}4 μm. A second cube must have a surface area to volume ratio 100 times as large as that of the first cube.
1 μm=1000 nm1\ \mathrm{\mu m}=1000\ \mathrm{nm}1 μm=1000 nm
For a cube, surface area to volume ratio = 6÷ 6 \div\,6÷ side length.
What side length should the second cube have?
4 nm4\ \mathrm{nm}4 nm
400 nm400\ \mathrm{nm}400 nm
40 nm40\ \mathrm{nm}40 nm
400 000 nm400\,000\ \mathrm{nm}400000 nm
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.