A technician takes samples from four calcium chloride stock solutions. The relative formula mass, MrM_rMr, of calcium chloride is 111.
| Sample | Volume of sample | Concentration of stock solution |
|---|---|---|
| P | 50 cm3 | 0.200 mol dm−30.200\,\mathrm{mol\,dm^{-3}}0.200moldm−3 |
| Q | 100 cm3 | 11.1 g dm−311.1\,\mathrm{g\,dm^{-3}}11.1gdm−3 |
| R | 100 cm3 | 0.200 mol dm−30.200\,\mathrm{mol\,dm^{-3}}0.200moldm−3 |
| S | 50 cm3 | 0.200 g dm−30.200\,\mathrm{g\,dm^{-3}}0.200gdm−3 |
Which shows the two samples that contain the same amount of calcium chloride?
PPP and RRR
PPP and QQQ
PPP and SSS
QQQ and RRR
151 exam-style questions on Edexcel GCSE Chemistry 6.2 Quantitative analysis, covering 6.2.1 Concentration in mol dm⁻³ and titration calculations, 6.2.2 Percentage yield and why actual yield falls short, 6.2.3 Atom economy of a reaction, 6.2.4 Choosing a reaction pathway, and 6.2.5 Molar volume of gases and Avogadro's law. Each one has a worked solution and a mark scheme showing where the marks go.