4   2 This question is about the elements in Group 2 of the Periodic Table. (a) Magnesium powder is added to a beaker of water containing a few drops of Universal Indicator. The apparatus is set up as shown and allowed to stand for a few days. test tube filled with water water and Universal Indicator filter funnel magnesium powder State two changes that will be seen after a few days. (2) .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... (b) Explain how the trend in the reactivity of the Group 2 elements is determined by their electronic configurations. (3) .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... Turn over 5   (c) Calcium reacts with chlorine. Ca(s) + Cl2(g) → CaCl2(s) Explain, in terms of electrons, why this is a redox reaction. (2) .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... (d) An experiment was carried out to determine the molar volume of hydrogen at room temperature. 0.035 g of magnesium was added to excess hydrochloric acid and 32 cm3 of hydrogen was produced. Mg(s) + 2HCl(aq) → MgCl2(aq) + H2(g) Calculate the molar volume of hydrogen from the results of this experiment. Include units in your answer. (2) (Total for Question 2 = 9 marks)