(Solved): 1. Magnesium nitride reacts with water to form magnesium hydroxide and ammonia. a. Balance the reac ...

1. Magnesium nitride reacts with water to form magnesium hydroxide and ammonia. a. Balance the reaction equation. (2) Mg3N? + H?O Mg(OH)? + NH3 b. Calculate the number of moles in 0.263 g of ammonia gas. (2) c. Hence, calculate the number of molecules of ammonia in the 0.263 g. (2) 2. Zinc chloride can be prepared in the laboratory by the reaction between zinc oxide and hydrochloric acid. a. Write an equation for the reaction. (2) b. A 6.75 g sample of zinc oxide was added to 100.0 mL of 1.20 mol L-1 hydrochloric acid. i. Determine the limiting reagent. (3) ii. Calculate the mass of zinc chloride that can be produced. (2) iii. Explain one systematic error that could occur during this experiment. (1) 3. A compound contains 36.5% of sodium and 25.5% of sulphur and the rest being oxygen. a. Use this information to determine the empirical formula of the compound. (3) b. When the compound reacts with excess hydrochloric acid solution, aqueous sodium chloride is formed and sulphur dioxide gas released. Write an equation to represent this reaction (include states in your answer). (2) 4. Magnesium has three isotopes; 24, 25 and 26. The relative abundance of the magnesium isotopes are 78.60%, 10.11% and 11.29% respectively. Calculate the relative atomic mass of magnesium. (2) 5. The following pieces of glassware are used in volumetric analysis. a. Name each piece of glassware. (2) CDII O b. In an experiment, glassware A was used to transfer 25.0 mL of 0.200 mol L-¹ hydrochloric acid solution into glassware B. i. Describe how A should be rinsed. (1) ii. Describe how B should be rinsed. (1) iii. Indicate on the diagram below, how the meniscus should sit on the calibration line of B for correct dilution. (1) H i. Calculate the concentration of the hydrochloric acid in B after dilution, if the volume of B is 100 mL. (2) 6. A 10.00 mL sample of sulphuric acid from a car battery was completely neutralised by 35.08 mL of 2.12 mol L-1 sodium hydroxide solution, by performing a titration. a. Write the equation for the reaction. (2) b. Calculate the concentration of the sulphuric acid. c. Explain one random error that could occur during the titration. (1) calibration mark