Bronsted-Lowry theory definition of an acid and a base

1.Give the Bronsted-Lowry theory definition of an acid and a base. Illustrate your answer with appropriate equations using one or more of the following compounds in each case. H2SO4, H20, NH3, NH4+ CH4, KCl, KOH, HBr (6 marks) 2.?(a) ?What do you understand by a conjugate acid-base pair according to the Bronsted-Lowry theory? (2 marks) (b) ?Identify the Bronsted-Lowry acid-base pairs in each of the following equations: (i) HCO3- (aq) + NH3(aq) ® NH4+ (aq) + CO32- (aq) ??(ii) CH3COOH (aq) + HCl aq) ® CH3COOH2+ (aq) + Cl- (aq) (4 marks) 3 (a) ?The ionic compound aluminium sulphate (Al2(SO4)3) is used in the treatment of water to render it suitable for human use. Write an equation for the dissociation of aluminium sulphate in aqueous solution and hence calculate the molar concentration of each ion in a solution of 0.137 mol dm-3 aluminium sulphate. (4 marks) 4. (a)?What is the difference between a suspension and a precipitate? Give a full discussion. (4 marks) (b) For the precipitation reaction: BaCl2(aq) + 2AgNO3(aq) ® Ba(NO3)2(aq) + 2AgCl(s) (i)?2.00 dm3 of 3.00 mol dm-3 AgNO3 was mixed with 3.00 dm3 of 1.00 mol dm-3 BaCl2. Show that neither of the reactants is in excess. (3 marks) (ii)?Calculate the concentration of each ion in aqueous solution after mixing. (3 marks) 5. ?25 cm3 of a solution of H2SO4 was titrated with 0.210 mol dm-3 NaOH. 19.5 cm3 of the NaOH solution was required to neutralise the H2SO4. Write a balanced equation for the reaction and calculate the molarity of the H2SO4 solution. (5 marks) 6. ?The ionic compound ammonium sulphate is an important fertilizer. Aqueous solutions of ammonium sulphate and sodium hydroxide react according to the following equation. (NH4)2SO4(aq) +2NaOH(aq) = 2NH3(g) + Na2SO4(aq) + 2H2O(l) (a)?(i)?Write the full ionic equation for this reaction (2 marks) (ii)?Write the net ionic equation for the reaction in part (i) and identify the Bronsted-Lowery acid-base pairs. (4 marks) (b)? A 3.00g sample of fertilizer containing ammonium sulphate was made up to 250cm3 of aqueous solution. A 25.0cm3 sample of this solution was added to an excess of sodium hydroxide solution and the ammonia gas produced passed into a solution of 50.0cm3 of 0.100mol dm-3 hydrochloric acid. The residual acid was then titrated with 0.100mol dm-3 potassium hydroxide 25.4 cm3 of KOH was required to achieve an end point. (i)?Write an equation for the reaction of ammonia gas with hydrochloric acid. (2 marks) (ii)?Write an equation for the reaction of hydrochloric acid with potassium hydroxide. (2 marks) (iii)? How many moles of HCl were present in the 50.0cm3 of 0.100 mol dm3 hydrochloric acid before the ammonia gas was passed through it? (1 mark) (iv)?How many moles of HCl remained in the 50.0cm3 of 0.100mol dm-3 ? ?hydrochloric acid after the ammonia gas was passed through it? (4 marks) (v)?Thus determine the number of moles of HCl that were used in the reaction with ammonia (2 marks) (v)?Use your answers to part (i) and (iv) above to deduce the number of moles of ammonia formed from 25cm3 of diluted sample of fertilizer (1 mark) (vi)?Thus calculate the number of moles of ammonium sulphate in the 25 cm3 of diluted sample of fertilizer (2 marks) (vii)?What amount ammonium sulphate (in moles) was present in the 3.00g sample of fertilizer? (2 marks) (viii)?What is the percentage by mass of ammonium sulphate in the fertilizer? (3 marks) Subtotal 56 + 4 marks for quality of presentation and awareness of use of number