13619.06R [Turn over 14 The Group II elements are known as the alkaline earth metals and they display trends in their physical and chemical properties. (a) State and explain the trend in atomic radius down Group II. [2] (b) The Group II elements react with oxygen to form the corresponding metal oxides. (i) Write an equation for the reaction of magnesium with oxygen. [1] (ii) The magnesium oxide produced in (b)(i) was added to a flask containing water and phenolphthalein. Suggest and explain, using an ionic equation, why the solution will change colour. [2] 13619.06R (c) Magnesium oxide may also be produced by reacting magnesium with steam. The diagram below shows the apparatus used in the reaction. magnesium HEAT HEAT damp mineral wool boiling tube delivery tube gas gas jar trough beehive shelf water (i) State why the damp mineral wool is heated. [1] (ii) State two observations which would be made in the boiling tube during the reaction. [2] (iii) Write an equation for the reaction which takes place in the boiling tube. [1] (iv) Suggest why the gas produced is collected over water. [1] 13619.06R [Turn over (v) The reaction was carried out using 0.08 g of magnesium. Calculate the volume of gas at 20 °C and 1 atm pressure that should be produced and suggest why this volume of gas was not obtained in the gas jar. Answer                         cm3 [3] (d) Group II oxides can react with dilute acids. Write an equation for the reaction between magnesium oxide and dilute nitric acid. [1]