A chemical plant uses a two-stage unit to dilute sulfuric acid. The sulfuric acid is a strong acid and initially has a pH of 1.
At each stage, a volume of solution from the previous stage is transferred and water is added to reach the total volume shown.
| Stage | Volume of solution transferred in cm3\mathrm{cm^3}cm3 | Total volume after adding water in cm3\mathrm{cm^3}cm3 |
|---|---|---|
| 1 | 25 | 250 |
| 2 | 10 | 1000 |
Calculate the pH of the sulfuric acid leaving stage 2.
Show your working.
A second solution used in the plant has a pH of 6.
Compare the hydrogen ion concentration of this solution with that of the sulfuric acid leaving stage 2.
112 exam-style questions on OCR GCSE Chemistry 3.3 Types of chemical reactions, covering 3.3.1 Oxidation and reduction in terms of oxygen, 3.3.2 Acids, alkalis and neutralisation, 3.3.3 The pH scale and measuring pH, 3.3.4 Oxidation and reduction in terms of electrons, 3.3.5 Dilute and concentrated, weak and strong acids, and 3.3.6 Hydrogen ion concentration and pH. Each one has a worked solution and a mark scheme showing where the marks go.