XMS SEC 3 WA3 2022 QP

3 6092/Chemistry/2022 Term 3 Weighted Assessment Section A Answer all questions. Write your answers in the boxes provided at the end of the Section. 1 Copper(II) sulfate is made by reacting an excess of copper(II) oxide with dilute sulfuric acid. The excess copper(II) oxide is then removed from the solution. Why is excess oxide added and how is the excess oxide removed? Why add excess oxide How to remove excess oxide A To use up all the acid By filtration B To use up all the acid By heating C To produce water By filtration D To produce water By heating 2 The graph shows how the pH of soil in a field changes over time. At which point was the soil neutral? 3 Given a supply of magnesium carbonate, zinc carbonate, dilute sulfuric acid and aqueous sodium hydroxide, how many different salts can be prepared? A 1 B 2 C 3 D 4

4 6092/Chemistry/2022 Term 3 Weighted Assessment 4 The diagram shows two experiments on a powdered oxide. In both experiments, the powdered oxide reacts and dissolves. What could the oxide be? powdered oxide reason A potassium oxide potassium oxide is basic B silicon dioxide silicon dioxide is acidic C sodium oxide sodium oxide is neutral D zinc oxide zinc oxide is amphoteric powdered oxide dilute sulfuric acid powdered oxide aqueous sodium hydroxide

5 6092/Chemistry/2022 Term 3 Weighted Assessment 5 Ammonium sulfate is heated with solution X and ammonia gas is given off. A piece of moist red litmus paper and a piece of moist blue litmus paper are held in the gas. What is solution X and what will be the colour change of the litmus paper? solution X colour change of litmus paper A an acid blue to red B an acid red to blue C an alkali blue to red D an alkali red to blue Question 1 2 3 4 5 Answer

6 6092/Chemistry/2022 Term 3 Weighted Assessment For Examiner’s Use Section B Answer all questions. Write your answers in the spaces provided. 6 (a) Explain, in terms of ionisation, the difference between a strong and a weak acid. …………………………………………………………………………………………… …………………………………………………………………………………………… …………………………………………………………………………………………… …………………………………………………………………………………………… [2] (b) A sample of an acid contains 0.16 g of hydrogen, 0.96 g of carbon and 1.28 g of oxygen. (i) Determine the empirical formula of this acid. [2] (ii) The relative molecular mass of the acid is 60. Deduce the molecular formula of the acid. [1] [Total: 5]

7 6092/Chemistry/2022 Term 3 Weighted Assessment For Examiner’s Use 7 The table shows information on some salts and products that contain them. name of salt formula of salt name of one compound to make salt name of other compound to make salt use of