A company makes a spray that stops mud sticking to shoes. The table gives information about two coatings the company could use.
Table: The mass needed for each pair of shoes, the cost, and the number of washes survived, for two coatings
| Coating | Mass needed for each pair of shoes in g | Cost in £ for each gram | Number of washes survived |
|---|---|---|---|
| Nanoparticle coating | 0.20 | 1.50 | 20 |
| Fine particle coating | 4.00 | 0.05 | 5 |
Which statement about the nanoparticle coating is correct?
It costs less for each pair of shoes and it lasts longer
It costs less for each pair of shoes but it does not last as long
It costs more for each pair of shoes but it does not last as long
It costs more for each pair of shoes and it lasts longer
40 exam-style questions on AQA GCSE Chemistry 2.4 Bulk and surface properties of matter including nanoparticles, covering 2.4.1 Sizes of particles and their properties and 2.4.2 Uses of nanoparticles. Each one has a worked solution and a mark scheme showing where the marks go.