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(a) In an experiment to standardise a solution potassium hydroxide (KOH) using a standard solution of sulphuric acid (H2SO4), the following procedure was carried out 25 cm of the KOH solution whose concentration was to be determined, required 27.0 cm of a standard sulphuric acid solution containing 2.940g sulphuric acid per 250 cm", for complete neutralisation. Methyl orange was used as the indicator (2 marks) Write a chemical equation to describe the reaction. (ii) Describe in detail how the standard solution was prepared? (2 marks) (ii) Calculate the concentration of the KOH solution in mol. dm' and g dm3 (8 marks) (iv) How was the burette prepared for the titration? (2 marks) (b) What volume of 0.01M sodium carbonate is required to neutralize 25 cm of a sulphuric acid solution containing 0.98 g per 500 cm of solution? (5 marks) (c) Calculate the pH of the following solutions; (1) A solution containing 3.99 g sodium hydroxide in 510 cm'water. (11) 10 cm 'of a 0,05 M solution of sulphuric acid. (iii) A solution of 1.39 g potassium hydroxide in 100 cm water. (iv) A solution made by mixing 90 cm' of a SM HCl solution with 30 cm' of an 8M monoprotic strong acid solution and making the mixture up to I litre with deionised water. () A solution of O.IM HCOOH given the ka - 1.7 x 109 (10 marks) (d) What is the Bronsted-Lowry definition of an acid? (2 marks) (e) Write an equation to demonstrate the reactions of a strong mono-protic acid and an alkaline- earth metal. (2 marks)