A technician prepares a reference solution from a strong acid. They dilute 25 cm325\,\mathrm{cm^{3}}25cm3 of the acid, which has a pH of 1, with water to make 250 cm3250\,\mathrm{cm^{3}}250cm3 of solution. They then take 20 cm320\,\mathrm{cm^{3}}20cm3 of this solution and dilute it with water to make 2000 cm32000\,\mathrm{cm^{3}}2000cm3 of solution.
What is the pH of the final solution? Show your working.
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.